I've been down this road before. What happened to me was that the bracket that the pushbutton was mounted to the car to broke. I tried to reach it from the bottom and had no luck. I was going to pull the pins on the hinges to pull the hatch off but after much fiddling about it popped and I opened the hatch. I would use the search function here. When I posted this last year when I had the same problem, many Pantera Brothers posted pictures and good advice. I my case it had nothing to do with picking the lock. The actual mount for the pushbutton broke. At the time I thought it might be the switch.
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