taking off the inside hatch panel as roadrunner777 described is the only way I know of. I had to do it myself after a friend of mine bought a boat, asked me to tow it I said yes. The guy he bought it from put it on the hitch and I did not check it before taking off. Three blocks later I was rear ended by a boat!! Minimal dent in the hatch and it was stuck closed.
You have to remove the 4 plastic screws at the top inside of the hatch, then remove plastic cover over the lock pull pin, then remove the screw inside and the plastic lock pin cover. Then on the inside handle/leash there are two screw to remove. You are now ready to remove the inside cover and it is tricky with the hatch closed, the top will pull straight out, but the bottom needs to slide upwards. there are two little feet that slide into the sheet metal inside the cover so you will have to push the plastic up far enough to clear the feet from the metal.
Or you can try to push/pull on the handle of the hatch and turn to the left/right at the same time. There are knobs or plastic studs on the back side of the handle that push/pull the rods on the inside of the door to unlock/lock, If the dent pushed the handle too far back that the knobs wont be properly aligned and the door will not release. This may re-align the knods and unlock/pop the hatch.
Yes I know my description is a little hard to understand, but it is the best I can do without having pictures. It sounds like a big job but is fairly simple. The toughest part is trying to get the inside hatch cover out without cracking it. Hope it helps and by the way Welcome to the forum and just think of it as you first upgrade or project on your explorer. GOOD LUCK.