That won't work as long as more than 1 shot has been taken, you can't have someone jump in after 2 holes or even 2 shots.
I agree quitters are annoying, I had someone in a 4 ball quit after the first hit the other night. Drove in a bunker and that was that. I don't expect they would have brought much joy to the game anyway, not with an attitude like that.
In this situation it would be nice to invite someone else since they could drive off and we'd all be at the same point in the round.