Well... I explained all this in my previous post, but I'll try to be more clear.
No... As I explained earlier, the guarantor is either subsidiary -- the creditor goes after him AFTER the assets of the principal debtor are finished -- or solidary -- the creditor can go after at his convenience --, but the principal debtor is always the principal, and the creditor can always go after him in any circumstances.
Of course, if I have a debt, and Elon Musk is my solidary guarantor, the bank will probably try to settle my debt with his assets, but, in the case of Derek and Maya who have nothing but what Patrick gives 'em, the bank wouldn't be bothered to go after them. In fact, the bank wouldn't even accept 'em as guarantors because they have no assets. (Well... Maya has nice assets, but those kinds of assets -- even Derek's -- would only be accepted as collateral by loan sharks...)
No. The debt is not transferred to the guarantor. The debt is transferred to the estate. The guarantor keeps his position as guarantor, either as solidary or subsidiary, and never becomes the principal. But, for the sake of argument, even if it were the case, it would make no difference: the assets would be the same -- Patrick's car dealership business (as you claim; I didn't check if it's his only asset).
Then, only what's left to your theory is the bankers, as good Samaritans as they usually are, would allow Derek and Maya to keep the business to pay for the debt with their work... But that would never happen in the real world. It would be like "trading a bird in the hand for two in the bush." (Though, if Derek and Maya are really guarantors, anything can happen in the BaDIK world... However, a crane the size of the Empire State would be necessary to suspend my belief.)
P.S.: I think this answers everything, so I won't bother about the last paragraph, though I don't know if Patrick loves Helen more than anything or if he tolerates her due to a sense of religious duty. That's another topic though, and it's too subjective for me to bother, differently from the credit situation.
P.P.S.: Now, I'm thinking, maybe Patrick really borrowed from loan sharks and left Maya's "assets" (emphasis in the first three letters of the word) as collateral. It will add a more interesting twist to the game and turn its finale into the fight against netorare -- if you lose the most difficult brawler fight ever, loan sharks will sodomize your love interest.