Do not do what your friend suggested. That makes it antagonistic from the get go. Remember, if you start nice in a negotiation, you have a place to go. If you start rude/demanding/or hostile, you have nowhere to go.
I say go with the loan lady suggestion. You start neutral and get a read what he is thinking, if anything. You can always add detail later.
He wants two things presumably: 1. Off the loan; 2. Some cash.
My guess is that he also wants: 3. D4 to have a stable home; 4. Not to feel like a real dirtball to Can.
Therefore, don't go with dad's suggestion. With interest rates, etc., a new loan is the way to go. Forget the old. Don't bring up the past. Look forward, and not back. Likely less guilt for him. Use the debts as negotiation against the payout price.
Then if and when he responds. Ask him what he wants to do before you tell him anything. That's your only chance to potentially hear that. You can always tell what you want or what the concerns are with his approach.
