Again, isn't this something the Insider Team can do by using my email address (my Microsoft account) and setting my participation to Beta? We were able to do that in 06 so I assume it's only gotten better since. Or one would hope.
If you can address the last issue I'd appreciate it.
Hello Richard,
That is something that is not possible to do. Like yourself, we are all Insider volunteers trying to help others with any issues as there is no official support. We are not MS.
Another example of this is the verify issue. This was fixed by MS back with build .71. Some are still facing this. They refuse to start fresh, so not much one can do. I have done over 30 clean installs in past couple months in the 8 vm's and couple spare laptops. It verifies the account every time. Originally had same issue.
Did a clean install again today, to my surprise, all 3 channels were open and selectable. Put this one in Release Preview as have not heard that was officially done other than for commercial.

This just might be the best way for you going forward. You can also run W11 without joining Insider if you prefer, you still get the CU updates, but not all the Store updates as in new Snipping Tool. They will all come after Oct 5th if not sooner. I personally have found doing the upgrade from W10, system never worked as well compared to the clean.
A clean install takes me about 7-10 minutes to run. only use a few programs on test machines so after setting my preferences, winrar, an uninstaller and a utility program, said and done in under 30 minutes. Faster than doing a major build upgrade.
On the working desktop, even though all data is stored on secondary drives, it can take me days to install everything I use. Especially the big stuff such as Autocad and Photoshop, Office etc.
I highly recommend going this route, you have already spent enough time on this issue. Nothing ever beats a clean install to get system working at its peak. The Insider Beta ISO of 22000.132 most likely be the same as Release ISO as MS did with 21H1. They will only compress install.wim to install.esd for MCT so consumers can fit on flash cards. Have already done that for bootable flash. One can split the install.wim file as well to fit on flash FAT32.
Good luck on whatever you decide. Take care.
Regards,