Hi scott,
Your tablet underwent an absolute shocking experience... Although you let it dry, there might still be water in the tablet, possibly on the motherboard/under metal covers and in other angles.
I recommend using [guide|9623|the teardown guide here on iFixit] and completely disassemble the tablet. Then put the motherboard into a bath of isopropyl alcohol (90%) for about 15 minutes (this will draw out every possible rest of water from everywhere). Then let it dry for about two days. Also, let all the other part sufficiently dry, possibly next to an air conditioning.
Then assemble the tablet. Now check your tablet again.
If there is still no sign of life, I would replace the battery next and then check the tablet again.
Please keep us posted.
Steffen