First, this is an interesting article.

Here I like to make some comments from different view points.

Credit Card: I do not think you can walk away without paying your credit card dues, unless you file bankruptacy. Credit risk has two sides. If you default, then you would not pay your money back. If bank default, you still have to pay your money back. Don't worry, someone would find your records and ask you to pay money back.

Bank loans: I do not think banks like to lend to money losing firms. If they have to, they would ask for collateral assets. When a firm goes under, the bank loans usually have highest piority to get money back.

Public firm funding: public traded firms funding includes stocks, bonds and bank loans. GM and F issued a lot of bonds for their funding. Bond buyers take higher risks for higher bond yields. Personally, both GM and F would be belly up. It is when issue, not whether issue.

Just my personal opinions for your reference.