im pretty sure the person who bought it will come back to claim it. he did paid a shit load of money. he could take you to court and end up just paying for what ever it is you paid for to get it towed/bonded. if he has a bill of sale and title signed by you its enough proof you sold him the truck.
now cops called you because u didnt clear your name at the dmv. if you had the cops would kept it and if no claim, off to the auction the tahoe would go. and hope they dont/didnt find drugs because you my friend will be in trouble.