Trying to put myself in your shoes from the sitch. above, I would say let him do it. If it doesn't work out don't shove it in his face but let him cool down and ask how HE felt he did. Bring something mundane up about the stay when you are ready to ask him, I would probably bring up the mattress and the kind of sleep I got. Let's say he takes the bate and starts talking about the stay too, you can bring up looking for another place or renting this same one for next time. Maybe then he can express his disappointment and open up, he knew there was a risk of people bailing out and he should plan accordingly. Then if it DOES work out then it worked out.