I thought I'd enter a new data point.
I have the same problem as most of you that weren't able to successfully debrick the touchpad (keep getting the openmulti error, cannot write tz.ebm aborted, etc...). So I cracked open the Touchpad.
The first thing I did was replace the battery with a full charged one. Did not work. I was hoping at least the battery pull would get the thing out of QDL mode (in which it seems to be permanently stuck). So another data point that simply replacing the battery may not fix your issue.
I'm currently running loopit.sh that is continually trying to execute tpdeprick.sh. Its been about 50 tries so far and no luck. Will post if anything else works. Currently it looks like the motherboard would have to be replaced if this doesn't work (this seems a bit pricey tbh).
Well I couldn't revive mine. I ended up purchasing a new motherboard (~$60) to fix this issue.