I'm feeling more human than most here. While I'm not disputing any of the points made above, USF1 must have quite a few employees (presumably somewhere between 50 and 100 and plenty more through companies who have contracts with USF1), the majority of which will have had no idea of any scheduling problems or the complete mess put in place by those upstairs. Yes the place should have been given to someone with a half decent chance of being on the grid in the first place (Prodrive, Epsilon, etc), but that decision has long passed.
There'll be plenty of people at USF1 who are slugging away without much hope, and it's them that I feel sorry for.
The only sensible decision, if you take the tiny knock of reputation out of things, is to give the USF1 spot to Stefan and, if there is space, allow USF1 the time to get their act together and only enter once they are ready - be that at the end of the season or at the start of the European season (which isn't going to happen - they have no drivers and their main backer has left).
Are we presuming that Campos will now be ready for Bahrain? Unless they've had the chassis for a while (but refused permission to use them until money turned up), then it's a hell of a job to get everything ready in the remaining 2 and a half weeks.