had this same problem with the MBP 16:
- installed latest Catalina drivers for UFX
- after installation, I followed instructions for the Security & Privacy panel
- allowed system reboot via dialog box
- OS apple load screen hangs at at 99%
i tried your solution above but didn't work for me. (what are the "recovery options"?) after multiple reboots, i ended up reinstalling Catalina from the recovery screen (instead of quitting the install process), and now it seems to work.
Catalina so far has really been a huge disrupter to workflow and productivity on just about every level. I highly recommend staying away for now.