Success! ...so far.View attachment 2365495
I was able to get another to load the Internet Recovery Mode and start installing the MacOS. Since this one has a 512 GB SSD, I may consider using this one as a work computer, for running the latest version of Apple Configurator 2 and any future reviving and restoring of Macs with T2 chips, now that my 2015 Retina 15" MacBook Pro can't run the latest Apple Configurator and doesn't have Thunderbolt 3. (For now I have to bring my M1 MacBook Air into work for this.) But the first attempt at this, it hung at "Less than a minute remaining..." while the status bar was nearly halfway through. This second attempt after resetting the NVRAM and SMC and rebooting the Air, I started the second part of the install a little over and hour from posting this, and the bar went all the way to the end, but it's still seeming to hang there. I'm gonna let it sit this way through most of my shift to see what happens next. If it's not done anything before I punch out, I will reset the NVRAM and SMC, and reboot the Air again and see if that does anything overnight.
After letting it run overnight, I came in this morning and was greeted by the language selection screen after the install completes. Now I'm logging it into the test account I made to check it out further.