How badly over leveraged is he?
It's interesting. He's wanting a bond company (or companies) to put up the money. He would need to give them collateral of 120%. He's saying that almost all his money is tied up in real estate and that these companies have a rule that they won't take real estate as collateral. I find that a bit hard to believe. I think the problem, as you suggest, is that they won't take Trump's real estate as collateral, because it isn't worth anything once you take account of the debt.
The wonderful irony is the reason he has been fined all this money is for overvaluing his properties to get bigger loans.