This has probably been pointed out already, but when "weaver's brother" (the pink dude with a shotgun you can get from one of the secret buttons) dies in a vehicle he becomes perma dead and there is no way to pick him up or respawn him. This used to be the case for all companions though now it only seems to happen to the pink guy. Just thought I would put it out there so you can look into fixing it.

If there is something about him that makes him different from the other companions for some reason then maybe fix it by making it so whenever you push the button he gets removed from the map and respawns at the button again?