Ever since then I've been trying to revive it. For awhile it would give me the battery symbol with a question mark, and then it changed to a different symbol, and then no symbol. I did some homework and tried using TPDebrick, but that doesn't seem to have fixed it. I also read that since the battery was dead, I could replace it with a new battery and it would likely fix the problem.
Unfortunately, after replacing it with a new battery from eBay, it still doesn't work. I've got the Touchpad (with the new battery) on the charger from the wall right now, and if that doesn't work overnight I'll try the Touchstone again in case the USB port is broken (I don't think it is because the Touchstone didn't charge the old battery after it completely drained.)
Anyone have some patience to help me bring this back from the dead? I still haven't snapped all the tabs in so I can open it up again easily in case there's something I need to do hardware wise. Also, this all started weeks ago -- prior to replacing the battery I left it on the wall charger and Touchstone for many days.