Car stolen in Poland !! and reappeared at the border with Ukraine

Moin, maybe this doesn’t belong here, but I hope you can help me anyway. So to the story: On 26.12.04. was stolen my colleagues in Poland his car ( Audi 80 ). After recording personal data and driving data a protocol was created with the police, however the official said that there is little chance of success to find the car. So far so good, so my colleague with wife and two children came back by bus to D, and here the theft at his The car was duly registered in January, and he has bought a new car. Now he has received a call from a company from Hanover to secure his car at the Polish/Ukrainian border. Now he offers in this company, which they will transfer the car to D for 300€, and at the same time take care of all the papers. But since he has a new car he wants to of course the old ni What does it look like now when he brings the car to D. What does he have to do to sell the cars? ( TÜV new or completely new FIN ? as the old one probably cut out). And it is worth it at all to bring such an old car (Bj. 91) back to D? or should he sell the box over there? Thanks in advance greeting from Hamburg