One Last HTC Thunderbolt Software Update Leaks Before Launch - Droid Life: A Droid Community Blog this should be the correct firmware.
If you're still having trouble I'd go talk to the andIRC guys over at xda
i tried just reflashing the downgrade firmware alone (most of step 4) and that didn't work so i did steps 1-3 then just the flashing part of step 4.. That worked except i was on the old software so i looked at the link he posted which is apparently a very new firmware, so i just found a non-chinese link then downloaded it and reflashed and now all is back to stock and i have a new software number (1.12.605.9) which is newer than the one that comes on the phone from verizon..which you can download here ( MultiUpload: Multiupload.com - upload your files to multiple file hosting sites! ) without having to decipher some chinese website. then Rename it PG05IMG.zip, drop it on the sdcard, reboot and hold down volume down
I was curious about this process as well. If we reflash to the production RUU we will be badck to normal as well as s-off?