Emergency Help required

I have a Audi A8 1997 model. My problem is that the lock mechanism for the trunk/boot has developed a fault and I can now not open it with the keys. The reason it is an emergency is that the battery is located in the trunk/boot on the right side and it has gone completely flat in the recent cold weather. I need to gain access to the trunk to replace the battery before the end of April because my road fund licence needs to be renewed for May, however this is not possible without a valid road worthy certificate. If I cannot find a solution quickly, the authorities will tow the car to a pound and rack up expensive storage charges and release fees. Is there a way to gain access to the trunk without having to distroy the lock or the inner light lens, paying for a lock smith to break in at great expense?

Can I jump-start the car to get it to a garage, how do I do this without getting access to the battery?

Text me with any suggestions on 07966468114 or reply to this message in the forum please. I really hope someone one here can help me out with some solutions.