I'm not sure that's a proper application of Too Big to Fail. Boeing is a systemically important company, but there is not much of a contagion risk in a Boeing Chapter 11. When a large financial company fails, all their counterparties are left in the lurch.

The government would absolutely provide debtor-in-possession financing if no one else would, but even that is extremely unlikely, since there are so many saleable assets.

It seems pretty likely to me that the government would prefer a Chapter 11 restructuring.