I have seen it twice, out of maybe 30 times. Both times I had pulled him into the empty starting room to get rid of his adds. Later, after taking down Brom and the King, it showed that there were still bad guys, so I remembered that Meathead's adds were still there. I went in to finish them, and Meathead had respawned.

It's not a high priority bug. In fact, I wouldn't mind if Meathead's Deli became a respawning map. Just don't put the respawn speed to high, as it is in FH:4, please. About half that would be fine. Thanks.