Why Won't My Prestige Pro 9D Power On (Despite a Full Battery)?

In September/October of 2014, I acquired a Visual Land Prestige Pro 9D and it was working until late December (the 24th, to be exact).

I tried powering the tablet up from nothing, but it wouldn't. I held the Power Button for about 7 seconds and I got the screen to power up (it started on the tablet maker's logo screen). I let go, and it shuts off like it never happened. Same applies if I keep pressing it down (after a total of 10 seconds, including the 7 it takes for the screen to turn on).

Figuring it was a dead battery, I put it on charge all day (about 6 hours total). Surprise, it still does it.

It's the 25th now, and I've either had it on charge or trying to turn it on. At this point, the screen won't power on no matter how long I try.

So far, I've tried charging it (6-hour stint on the 24th and an overnighter after that), pressing the Reset button on the back (yeilded the same result of 'hold the button, powers off no matter what'), and attempting a memory wipe (which, at the time, the screen wouldn't power on with both buttons pressed; and now can't be done).

I've scoured all over the Internet to no avail (it seems like everyone has a solution for the Pro 7D, but not for any other member of the Visual Land tablet sets), and that's why I'm coming here.

Has anyone had a similar experience and how have you fixed it, if you have?