Given how much of everything moves based on short-term credit, it is unlikely anybody would have been able to step in before the economy imploded. The credit crunch was not about being able to get funds to build a new building, it was about being able to get funds to ensure the shipment of raw parts was sent (taken recursively through the entire supply chain all the way to your local retail outlet).
If that had seized, it would have been far worse than the bailouts.
Unfortunately, there should have been at least civil penalties (and probably criminal pentalies) associated with building and hiding enough toxic assets to tank the banking system. The real travesty was not the bailout, it was that there were no negative consequences (relatively speaking) to the people who caused it (which is a tough question to answer, but not enough effort was made, IMO).
I don't think you understand how everything is plugged into the credit markets and banking systems. I suggest you read Sorkin's book a as starting point.
Citation needed.
There would still be demand that needed supplying, no? Some non-criminal companies would have happily stepped up to fill that void.