Ref: the import broker...
Do these two statements contradict each other? Did you use a broker or not? :S
The problem is that, on the DoTaRS website, all M35s are listed as being eligible, which given that information as well as what he was told from the workshop themselves, he could rightly assume he could find whatever one he liked. Perhaps DoTaRS also need to look into how they display their information on the website (and perhaps autech_axis, you lawyers might consider listing them in any legal action)
Did I read somewhere that the workshop offered to buy the car back off you? Wouldn't that be far cheaper than taking them to court? I know there are principles at stake, but it might wind up causing you a lot less grief in the long run, given that one of your suitable resolutions was to be paid for all costs incurred so far. Are they offering to pay you what the car owes you?
I can understand how this drama must be fairly gut-wrenching for you guys though, having such beautiful cars in your possession and not being able to drive them fully registered.