Question – Thumbnails are not displayed at all

I want to use Yarpp as a sidebar widget but thumbnails are not displayed at all thoug, my question is not about that.
I know what is the problem, I have a theme that doesn’t use wordpress default featured image but a custom one called with <?php tfuse_media(); ?> .

Yarpp can work with WP themes like that? And if I can’t find a solution here can you tell me atlast what plugin file I need to modify to try and tweak it myself?

https://www.ads-software.com/extend/plugins/yet-another-related-posts-plugin/