Harry, if you had the car at BHM for them to sell on your behalf then there is no contract with the buyer until you accept it.
With what has happened it is a horrible position to be in, for all of us with kids losing an unborn baby is something we never want, but you and your wife are not alone...and we are all thinking of you both.
So, I'd tell the trader that there is no sale agreement and he will have to take it like a man and piss off.
