Movie thumbnail not metadata image

Let me start by saying I’m not a metadata expert. All of my movies are stored on a local NAS drive. I have disabled metadata fetching from the settings. However, I cannot get the app to display the movie artwork that “I think” is embedded in the file. To expand on the “I think” comment. I have all of these same movies loaded into iTunes. From within iTunes, I add artwork to each movie so that the actual movie cover is displayed. Also, from within VLC player on my PC if I display the media info it displays the artwork that was added from with iTunes. All of that to say I “believe” the artwork has been embedded in the file by iTunes. What infuse actually displays is just a random frame from the movie as the icon. Am I way off base?