There is a link from the button mechanism down to the latch that has plastic clips on either end. When the plastic clip and the hole wear a bit, the clip pops out of its hole and the link just dangles.
On e36 cars with fold down rear seats, this is no problem. You just crawl in the trunk and snap up the trunk lid liner and reach in and pop the trunk. Then replace the plastic clips on the ends of the link. My daughter did this on her '97 last year.
In your case, you will likely have to find a round rubber sheet metal plug at least a half inch in diameter. Then remove your license plate and drill a hole that fits your plug near the center of the license plate. Then reach in with a hook and release the trunk lid. Then repair. I have not done this, but it is the only solution I can think of.