I used to work for one of the large banking institutions...
Just a heads up to the OP & anyone who is curious...
MOST IF NOT ALL BANKS IN THE US (excluding specific individual relationships one might have with their own institution, which varies based on individual customers, etc) WILL NOT TAKE any form of check, cashier's including...IF THERE IS MORE THAN 1 PARTY NAMED ON THE CHECK AND YOU ARE THE ONLY ONE PRESENT, they will even question and make you sweat when both parties are there IN PERSON, because in banking this is a big red flag. The biggest red flag being the amount of the check, which if it's OVER 9k, will cause possible issue. There shouldn't have been both parties' names on that cashier's check...though it might be practice for that institution, you can request it be made out just to the individual and they shouldn't have issue with it.
OP- It is VERY plausible that the buyer did everything LEGIT, and responsibly, as far as he knew before flying out to you, and based on my professional experience, banks make these mistakes all the time, they should know based on the situation (buying a car out of state) that this would be a roadblock. And unfortunately, it takes time for the banks to pick up the pieces. They don't always drop everything for a customer immediately dude. It's EXTREMELY plausible that his intentions were true. And then also you obviously had no idea that a cashier's check isn't like cash, IN CERTAIN SITUATIONS, it just SECURES the cash, so the buyer couldn't pull it out before the check cleared. "The moment I see 2 people's names on that check, I say we gotta go to the bank together"
Then I read your responses in this thread, and honestly see the harassment and attitude you've decided to act with...IMO that's about the dumbest thing you could do to someone who has your car in another state, and is the gatekeeper to getting you your money. Yeah, you can go the police route, FBI, whatever, but it doesn't have to. Well, my bs detector has come on, and based on how you've responded, you've taken the aggressive route. Now he's taking his time, and it pisses you off because you probably jumped to offend/threaten him early on by judging the entire situation too quickly...you would probably do equal in the same position.
He will not get charges pressed against him, if it's the scenario I've painted, the bank can corroborate it, and honestly, you could be vulnerable to harassment charges yourself, if what he says is true.
So chill out, stop with the negative/aggressive energy, and be a little patient. IMO you put this extra time waiting on yourself, though I know you don't give a rat's *** what I think, but maybe this will help YOU OUT in the future