Had the issue the other day with the trunk getting full of water an killing the CL pump, when all the doors and hatch were locked.
Turns out if you remove the drivers side license plate lamp, you can use a long thin screwdriver to push the trunk latch pawl under the handle (similar to what the actuator does), and thus get the trunk latch to open.
Attached is a picture of the lock (viewed from above), and I have tried to indicate where to put the screwdriver, in order to push the pawl under the handle.
It is almost impossible to see in there, so it is done mainly by feel.
Hope I have conveyed the procedure, and that it may help someone in the future.