yes it is possible to remove the majority of the hatch trim to gain access to the locking mech without breaking it, BUT ! IIRC there are two screws on the lower/bottom outer edge of the hatch and two more holding the internal pull handle recess in place! so you will have to unclip the trim from around the bottom of the rear screen and pull it away from the hatch far enough to give you room to reach in and manually trip the locking mech! it can be be done

but it's a fiddly operation and could result in blood loss on your behalf

Ihave have done it a couple times on vehicles in breakers yards while gutting them for parts

when either the battery is missing or there are no keys for the car

Ifind dropping a good torch into the hatch gives you enough light to see what your doing as you will only have enough space for one arm to with inside the trim panel or you may damage it! good luck and top up on sticky plasters before you start
