What if an Add a cover button were added to the song page, next to Add new translation?
It would open a form for video URL, artist name, and maybe comments limited to a certain number of characters. It would attach to the song page as "contributed by [subscriber name]". Maybe the video image could be smaller and positioned down by idioms.
No points. It would be only for the purpose of sharing someone's favorite.
(Bad idea? Too messy? It won't hurt my feelings.)
While we're on the subject, if a duplicate song name is entered, a message could pop up as "Another song of that name exists. Please see if it's a duplicate. Covers are not permitted unless by original artist." Subscriber clicks Ok to make box go away.