I'm sorry I got you location wrong, though the information I gave may help others.
I don't think you need to be overly concerned about the car, it seems to have plenty of scope for towing heavy caravans. As I think you have found the challenge is going to be the caravan and keeping it within its MTPLM.
Whilst the caravan manufacture does state the caravan's MIRO, to be honest that cannot be assumed to be accurate, due to manufacturing tolerances, and other imperfections including the weather it can vary. The only way of knowing it's weight is to measure it when it is truly empty.
The MTPLM is significantly more important. It should not be treated as a target value, you must aim to keep the caravans all up weight under the MTPLM. This is why ensuring you have the correct MTPLM figure is essential.