Spinning Wheel prevents login to Admin user but not other users (intel core i5, Big Sur)

Hello, I have a late 2014 Mac mini (Intel Core i5 running Big Sur 11.6).

I am transferring the data from this Mac to a different computer and am unable to login to the Admin account to access its data. This is the only admin account on the device.

When I log in to the Admin account, I get a spinning wheel for a very long time, followed by a forced reboot.

• Sometimes a window pops up that says "Your computer was restarted because of a problem. Click Report to see more detailed information"....but clicking report doesn't open any information.
• Sometimes I get two spinning wheels.....both a rainbow colored wheel and a black and white spinning wheel at the same time.

I can still login to the non-admin account on this device and have transferred all of it's data.

I have tried the following to fix the spinning wheel on the admin account:

• from recovery...running First Aid on the Mac HD, Mac HD - Data, and MacOS Base System. No problems.
• running Onyx utilities in the non-Admin account
• trying to start the Admin account in Safe Mode
• reinstalling Big Sur from recovery mode
• resetting NVRAM

Still seeing a spinning wheel and a failure to login to the Admin account.

Ideas:

1) try to install Monterey from recovery?

2) is there a way to create an additional admin account from recovery?

3) reinstall Time Machine backup from recovery

Any input is greatly appreciated as there are items not on iCloud I really hope to retrieve. I'm a little reluctant to go the Time Machine route unless there are no other options, just in case there are issues with the backup, and also because the backup doesn't capture the last month of data.

thank you for any input!