Who does Bottle & Cappy cheer up?

So I ran a mission and rescued Bottle & Cappy. They now show up randomly, and I've seen some people's happiness rise, one in particular went from 10% to 75%.

Now one of my quest runners (basically my Avatar in the game, so I keep a close eye on him). He recently died, and on revival, his happiness has dropped to 10%. Now, since he's one of my primary quest runner, he doesn't get assigned to a room.

So will Bottle & Cappy cheer him up while he's wandering around the vault?

I stopped playing this game, but a number of forums and Nukapedia seem to agree that they provide a vault-wide happiness boost upon appearing that wears off once they leave.

Nukapedia:

They provide a temporary 20% happiness increase to every dweller in the vault, regardless of which room Bottle and Cappy are in. After they leave, dweller happiness is returned to their previous level.