Rescinding A Bad Loan As Creditor

Hello, and thanks for reading. We were in a life-changing car accident in Costa Rica on vacation (a mountain road collapsed and we dropped 35 meters to a dry river bed.) My wife suffered an AOD (internal decapitation) and I destroyed my shoulder and elbow, plus multiple TBIs and associated TIAs. My wife had excellent neurosurgery at Perez Zeledon in CR and is one of the very few AOD survivors with no neurological deficit.

We sold our little CR house and came back to the US. We were in pretty bad shape and had to be medevac'ed home.

We sold our house for cash, as we had paid cash when we bought it. We got $200,000 for it. My 23-year-old son asked if he could borrow some to buy a truck. With our approval, he got $107,000 for the truck and $70,000 to hold for us as we changed countries. No contract was signed. No interest was charged. My son agreed to pay us back $3,000 a month, interest free, until the loan was paid.

He immediately became hostile, and took half the $70,000 and gave it to a girlfriend. Our medical bills here in NY are huge and our son refuses to help us with our scary expenses, even with his existing debt to us. My wife's AOD surgery was $400,000 as we were just tourists and not able to use the CAJA national medical system. We had to use a private hospital and pay the neurosurgical team ourselves in cash. That cost us our home in Weston, CT.

By my calculation, my son owes me $177,000, which he refuses to pay. We can address the larceny from the $70,000 later. He currently lives in Denver, but the arrangement was made in NY State.

I have decent legal knowledge but am certainly not an attorney. My plan is to send him a letter of recission, which gives him 20 days to completely pay back the debt. I realize a six-figure loan default, larceny from money entrusted to him (fraud), and additional thefts from our home in Weston would be very serious consequences to him, possibly life-destroying and I do not really want to go the legal route. I would prefer an amicable settlement.

Does my recission idea hold water?

Thank you all for your kind assistance.