I'm expecting to wind up in a similar situation eventually, so I've been thinking through and researching how to handle it. Maybe you'll find some of this useful:
My goals will be to keep them comfortable, keep them in their house, and protect my own family from the fallout as much as possible. Toward that end, I would
not wire them that money on Monday. I would take the day off work -this is a family emergency- and visit a bankruptcy attorney with FIL. (You might also be interested in some kind of elder care councilor because of your MIL's situation.) The bankruptcy attorney would be able to advise on the exact significance of that hearing, and help you plan a strategy around discharging the maximum amount of debt. Note also that bankruptcy puts them in credit jail. That could be a good thing.
In my state (California) there is a small homestead exemption on home equity. They would be able to keep that in bankruptcy. My concern with wiring them money right away is that it could wind up reducing their need for debt discharge as a bankruptcy proceeds. Personally, I'm not thrilled about the prospect of bailing out my in-laws, but I'll do it. They're family.
I will do everything in my power to avoid bailing out their creditors. Discharge as much debt as possible first. Then write checks.
Well, even before writing checks, I'd look into getting them on as many different kinds of necessary aid as possible. They paid taxes for decades to build our meager safety net, so there's no shame in drawing on it. Medicaid is a no-brainer in your in-laws' situation (and taking money from you right away could make it harder to qualify --again: I'd speak to someone in elder care.) Being mostly dependent on social security and with medical expenses, they likely qualify for SNAP.[1] I'd also try to find out if there's any way to take advantage of Section 8 (would they move? is there a way to tap housing vouchers for mortgage payments?)
With debt discharged and with the safety net taking care of as much as possible, then we'd look at what's left. They'll probably still need help to stay in the house, and we'll help with that. If a bankruptcy happened they'd be in credit jail, but we'd still have a talk about credit cards right away. An important goal for me would be avoiding the situation where our money is creating headroom in their finances for them to run up big credit card balances years later. My earnest hope would be that credit jail would give them time to permanently re-adjust their habits, but I'd also run credit checks occasionally to be sure. (YMMV.)
Anyway, your situation sucks. I'm sorry you're in it. I hope some of that is useful, and that you'll keep us up to date on how things play out. Good luck.
[1] This seems to have a lot of great information on SNAP eligibility:
http://www.ncoa.org/assets/files/pdf/center-for-benefits/SNAP-details.pdf