I ran into this same question when I was cleaning up the credits for Live Stiffs Live. The last song on the album is performed by all the musicians from the various bands on the tour and is credited to “All” or “Entire Crew”, depending on which release you’re looking at. After a discussion on the old forums, I changed the credit to Various Artists, with the appropriate artist credit.
In your case, I would probably leave the credit as “Various Artists” since there isn’t an artist credit on the release art. You’d probably want to put a note in the release’s annotation so future editors won’t immediately try to change the credit.