The article uses the word "guarantees." If that's an accurate characterization of what the bankers were told, the amount of money they are owed would make litigating a verbal contract worthwhile.

Elon is in this mess because he signed a contract on a whim and spent nearly a year trying to weasel out of it. Making the purchase of Twitter was an act of rage quitting litigation he was going to lose. So it's entirely plausible he's stepped in the same blob of poo again.