Jet A1 into diesel vehicles is one thing; quite possible but awareness of adverse side-effects (eg poor pump lubrication) is needed. Many an airport has used discarded Jet A1 in its fire tenders. If it all goes horribly wrong the vehicle coasts to a stop; embarrassing perhaps but no more.
Putting road spec. Diesel into a jet aircraft that uses Jet A1 means putting a fuel into an engine with a specification that the engine was not designed for. If or when it all goes horribly wrong people may die and others may go to jail. The basic product is pretty much the same, but it's the details in the Jet A1 spec that count, eg the additives.