Actually, I was able to unroot my HTC EVO V following this guide: http://androidforums.com/evo-v-4g-all-things-root/561781-evo-v-4g-ruu-flashing-guide-unroot-guide.html
Got it back to stock with a stocked rom and then rerooted it with just SuperSU, and this time, avoided Harmonia and all went...