There have been record temperatures all over the US. Perhaps a batch of these tablets sat in a non-regulated warehouse where it got really hot or perhaps were even stored on their sides instead of on their backs.
This might sound kind of harsh, but I'll bet if you warm the entire tablet to about 100F, place it into a ziplock bag (to control moisture), then place it face down in the freezer overnight, the glue will be so set by morning you won't have this problem again.
I think playing a movie or a game is KINDA getting it warm enough to soften the glue, but not hot enough to seat the glass completly. Maybe if you played a higher quality movie than Transformers.....
You can warm it to 100-120F by leaving it in your car on a sunny day with all the windows rolled up for about 30 minutes. Don't put in on the dash, but put it somewhere where the sun won't hit it and make sure it's face down so the weight of the tablet will press down evenly against the glass when the glue gets gooey. The floor of the front seat should do.
(You could also place it in the oven as long as you use bake instead of broil and place it the middle rack, an equal distance from the top and bottom heating coils. The temperature should be on WARM. That should be about 100-150F. If you have any doubts, place a piece of white bread in the same spot beforehand and see that it takes forever to turn in to toast.)
Then, wherever it lies face down, slip the ziplock bag over it while it's still warm and carry it face down by the edges of the bag, not touching the tablet itself. Lay it face down on a counter or a table till its closer to room temperature. Then pick it up by edges of the bag and place it in the freezer, still face down, onto a flat area where the weight still be distributed evenly.
When you take it out of the freezer a few hours later or the next morning, be aware that, even though the screen is Corning glass, it will still be kind of brittle until it warms back up to room temperature. Wait at least an hour before taking it out of the bag and fiddling with it.
This is only a suggestion. If I get mine tomorrow and it has this issue, that is what I am going to do.....as long as someone else tries it first.
If your tablet can't withstand a little heat and a little cold, then it's not even worth the small amount you paid for it. The battery might explode, but at least the screen will be fixed.
Enjoy!