Cannot get php code to work

Trying to get multiple authors to show below title of posts.

Theme: Neve pro

I believe I need to add the correct template tags in the php file located themefolder/inc/views/partials/post_meta.php

Content below

<?php
/**
 * Should handle post meta display.
 *
 * Author:          Andrei Baicus <[email protected]>
 * Created on:      28/08/2018
 *
 * @package Neve\Views
 */
 
namespace Neve\Views\Partials;
 
use Neve\Views\Base_View;
 
/**
 * Class Post_Meta
 *
 * @package Neve\Views
 */
class Post_Meta extends Base_View {
    /**
     * Function that is run after instantiation.
     *
     * @return void
     */
    public function init() {
        add_filter( 'neve_display_author_avatar', array( $this, 'should_display_author_avatar' ) );
        add_action( 'neve_post_meta_archive', array( $this, 'render_meta_list' ) );
        add_action( 'neve_post_meta_single', array( $this, 'render_meta_list' ) );
        add_action( 'neve_do_tags', array( $this, 'render_tags_list' ) );
    }
 
    /**
     * Show/hide author avatar based on customizer option
     *
     * @param bool $value option value.
     *
     * @return bool
     */
    public function should_display_author_avatar( $value ) {
 
        $show_avatar = get_theme_mod( 'neve_author_avatar', false );
 
        if ( $show_avatar === true ) {
            return true;
        }
 
        return false;
    }
 
    /**
     * Render meta list.
     *
     * @param array $order the order array. Passed through the action parameter.
     */
    public function render_meta_list( $order ) {
        if ( ! is_array( $order ) || empty( $order ) ) {
            return;
        }
        $order     = $this->sanitize_order_array( $order );
        $pid       = get_the_ID();
        $post_type = get_post_type( $pid );
        $markup    = '';
        $markup   .= '<ul class="nv-meta-list">';
        foreach ( $order as $meta ) {
            switch ( $meta ) {
                case 'author':
                    $author_email   = get_the_author_meta( 'user_email' );
                    $gravatar_args  = apply_filters(
                        'neve_gravatar_args',
                        array(
                            'size' => 20,
                        )
                    );
                    $avatar_url     = get_avatar_url( $author_email, $gravatar_args );
                    $avatar_markup  = '<img class="photo" alt="' . get_the_author() . '" src="' . esc_url( $avatar_url ) . '" />&nbsp;';
                    $display_avatar = apply_filters( 'neve_display_author_avatar', false );
 
                    $markup .= '<li class="meta author vcard">';
                    if ( $display_avatar ) {
                        $markup .= $avatar_markup;
                    }
                    $markup .= '<span class="author-name fn">';
                    if ( ! $display_avatar ) {
                        $markup .= __( 'by', 'neve' ) . ' ';
                    }
                    $markup .= wp_kses_post( get_the_author_posts_link() ) . '</span>';
 
                    $markup .= '</li>';
                    break;
                case 'date':
                    $markup .= '<li class="meta date posted-on">';
                    $markup .= $this->get_time_tags();
                    $markup .= '</li>';
                    break;
                case 'category':
                    if ( $post_type !== 'post' ) {
                        break;
                    }
                    $markup .= '<li class="meta category">';
                    $markup .= get_the_category_list( ', ', get_the_ID() );
                    $markup .= '</li>';
                    break;
                case 'comments':
                    $comments = $this->get_comments();
                    if ( empty( $comments ) ) {
                        break;
                    }
                    $markup .= '<li class="meta comments">';
                    $markup .= $comments;
                    $markup .= '</li>';
                    break;
                case 'reading':
                    if ( $post_type !== 'post' ) {
                        break;
                    }
                    $markup .= '<li class="meta reading-time">';
                    $markup .= apply_filters( 'neve_do_read_time', '' );
                    $markup .= '</li>';
                    break;
                case 'default':
                default:
                    break;
            }
        }
        $markup .= '</ul>';
        echo ( $markup ); //phpcs:ignore WordPress.Security.EscapeOutput.OutputNotEscaped
    }
 
    /**
     * Makes sure there's a valid meta order array.
     *
     * @param array $order meta order array.
     *
     * @return mixed
     */
    private function sanitize_order_array( $order ) {
        $allowed_order_values = apply_filters(
            'neve_meta_filter',
            array(
                'author'   => __( 'Author', 'neve' ),
                'category' => __( 'Category', 'neve' ),
                'date'     => __( 'Date', 'neve' ),
                'comments' => __( 'Comments', 'neve' ),
            )
        );
        foreach ( $order as $index => $value ) {
            if ( ! array_key_exists( $value, $allowed_order_values ) ) {
                unset( $order[ $index ] );
            }
        }
 
        return $order;
    }
    /**
     * Get <time> tags.
     *
     * @return string
     */
    private function get_time_tags() {
        $created  = get_the_time( 'U' );
        $format   = get_option( 'date_format' );
        $modified = get_the_modified_time( 'U' );
        $time     = '<time class="entry-date published" datetime="' . esc_attr( date_i18n( 'c', $created ) ) . '" content="' . esc_attr( date_i18n( 'Y-m-d', $created ) ) . '">' . esc_html( date_i18n( $format, $created ) ) . '</time>';
        if ( $created === $modified ) {
            return $time;
        }
        $time .= '<time class="updated" datetime="' . esc_attr( date_i18n( 'c', $modified ) ) . '">' . esc_html( date_i18n( $format, $modified ) ) . '</time>';
 
        return $time;
    }
    /**
     * Get the comments with a link.
     *
     * @return string
     */
    private function get_comments() {
        if ( ! comments_open() ) {
            return '';
        }
        $comments_number = get_comments_number();
        if ( $comments_number < 1 ) {
            return '';
        }
        /* translators: %s: number of comments */
        $comments = sprintf( _n( '%s Comment', '%s Comments', $comments_number, 'neve' ), $comments_number );
 
        return '<a href="' . esc_url( get_comments_link() ) . '">' . esc_html( $comments ) . '</a>';
    }
 
    /**
     * Render the tags list.
     */
    public function render_tags_list() {
        $tags = get_the_tags();
        if ( ! is_array( $tags ) ) {
            return;
        }
        $html  = '<div class="nv-tags-list">';
        $html .= '<span>' . __( 'Tags', 'neve' ) . ':</span>';
        foreach ( $tags as $tag ) {
            $tag_link = get_tag_link( $tag->term_id );
            $html    .= '<a href=' . esc_url( $tag_link ) . ' title="' . esc_attr( $tag->name ) . '" class=' . esc_attr( $tag->slug ) . ' rel="tag">';
            $html    .= esc_html( $tag->name ) . '</a>';
        }
        $html .= ' </div> ';
        echo $html; // phpcs:ignore WordPress.Security.EscapeOutput.OutputNotEscaped
    }
}

I’ve tried to change the “$markup .= wp_kses_post( get_the_author_posts_link() ) . ‘</span>’;” line to

if ( function_exists( 'coauthors_posts_links' ) ) {
    			$markup .= coauthors_posts_links() . '</span>';
					} else {
					$markup .= wp_kses_post( get_the_author_posts_link() ) . '</span>';
					}

which gets be the authors listed, but now in duplicate form with different formatting. I’m not very proficient at php. Any pointers would be much appreciated.

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