You still really think he did all of that only because of YC's ~6% stake in them?
AirBnB has raised $7.8M (at, what, around a ~$40M valuation at the time? 6% of which would be over $2m). Is it really that incredible that someone would send a few emails for a shot at that kind of money?
Which, again, isn't to denigrate him at all. He's obviously very good at what he does and deserves a lot of respect for it.