Hey @tdm. The folks over at the unofficial discord said this may interest you. I tried using the factory restore tool with both the July 2020 and October 2019 qfps to reflash stock from LineageOS. Pro1 got past boot splash, but then kept boot looping into the bootloader. Selecting "reboot to recovery" would loop right back into the bootloader.
I was able to flash the lineage recovery and get LOS installed again, so at least I can use the phone. Would like to have the option of getting back to stock though, and your factory restore tool seems like the best option. Thank you for putt