get video on place of featured image

Hi,
On this website https://194.150.248.140/~volvoar1/ wit Inspire wordpress theme there are featured images next to the posts.
It should be possible to add media there such as a video.
In the backend I can add a media link and it should be displayed but this does not work.
Maybe it is because of the code here

Inspire: functions_ajax_posts_classic_display.php

if (has_post_thumbnail($results_query[$i]->ID)) {
								printf("<a href='%s'>%s</a>",  esc_url(get_permalink($results_query[$i]->ID)),get_the_post_thumbnail($results_query[$i]->ID, 'archive_classic_img'));
							} else {

[Please post code & markup between backticks or use the code button. Your posted code may now have been permanently damaged by the forum’s parser.]

It looks like it looks for an featured image and if thats not there for an archive pic. Biut not for my media.
Anybody an idea how to fix this?
Thanks!!