I'd argue that raising money from YC (specifically) might be harder than raising money generally from angels/VCs.
There are still only a finite number of YC applications selected into every cohort (and my guess is, as the brand grows, the number of teams competing grows). But, the number of potential angels and VCs for a deal is not as constrained.
Summary: Getting into YC is not the same as raising money from angels/VCs. I wouldn't equate the two.
Same founders? Same project? Its important - this implies YC missed a golden opportunity - did they?
Further, was it typical of YC's space - web app, demo'able in weeks, two to 5 founders? If not, then its apples-oranges. Yes, you have to find your investor; YC may not be that investor.
