Plugin breaks checkout on PHP 8.0

Hi.

I manage a site that’s hosted on Kinsta. They’re forcing an upgrade from PHP 7.4 to PHP 8.0. I switched the site over to PHP 8.0, but can’t finish checkout due to an error with this plugin. Here’s the error log:

2022/11/09 13:02:49 [error] 68966#68966: *353376 FastCGI sent in stderr: "PHP message: PHP Warning: Undefined array key "epofw_data" in /www/****************/public/wp-content/plugins/extra-product-options-for-woocommerce/includes/class-epofw-front.php on line 866
PHP message: PHP Fatal error: Uncaught TypeError: array_key_exists(): Argument #2 ($array) must be of type array, WC_Order_Item_Product given in /www/****************/public/wp-content/plugins/extra-product-options-for-woocommerce/settings/epofw-common-function.php:2768
Stack trace:
#0 /www/****************/public/wp-content/plugins/extra-product-options-for-woocommerce/includes/class-epofw-front.php(869): epofw_check_array_key_exists('epofw_data', Object(WC_Order_Item_Product))
#1 /www/****************/public/wp-includes/class-wp-hook.php(308): EPOFW_Front->epofw_add_order_item_meta(41282, Object(WC_Order_Item_Product), 20761)
#2 /www/****************/public/wp-includes/class-wp-hook.php(332): WP_Hook->apply_filters(NULL, Array)
#3 /www/****************/public/wp-includes/plugin.php(517): WP_Hook->do_action(Array)
#4 /www/****************/public/wp-content/plugins/woocommerce/includes/data-stores/abstract-wc-order-item-type-data-store.php(60): do_action('woocommerce_new...', 41282, Object(WC_Ord" while reading response header from upstream, client: 86.32.58.126, server: ********.ie, request: "POST /?wc-ajax=checkout HTTP/1.1", upstream: "fastcgi://unix:/var/run/php8.0-fpm-hammockology.sock:", host: "www.********.ie:33922", referrer: "https://www.********.ie/checkout/"

Any ideas?
Thanks!