Hi,
If the trunk lock doesn't lock, the rest will pop open. The most common reason is that the wires to the lock break in the region of the hinge. Look at the left hinge bar; the wires are held in place by a plastic cover and then they emerge in a region that flexes. That's where they typically fail.
Look closely as it is difficult to tell. Grab each wire and tug to make sure it's okay.
Regards,
Adnan