Hi Paul, I think the popular response to your question would be to contact Motability and explain to them the issue. They are there to help and I’m sure that if some form of retrofit cannot be carried out, then a swap may be possible to a car with a powered boot with a low down sensor. Either way a discussion with Motability should help to get you into the vehicle you need.
Good luck.
? I will be remembered for nothing but had great fun doing it ?