I’ve no Idea tbh but I’d imagine this may raise a big red flag with motabillity and they may decide that both cars if they agree to it may need black boxes fitted.
Two cars one driver doesn’t make sense financially tbh unless say you have a small city car because you work in the city and your son needs a big 4×4 because his hobbies are in the country side.
As I say, to me it doesn’t make sense financially. Maybe a wee bit more information and hopefully someone could help.