Need to downgrade my laptop to Sequoia 15.0 but I don't have admin
My Macbook Pro 2019 upgraded to 15.1.1 and after the reboot, the progress bar is hung after 95%. Poking around, what I suspect is happening is that it's trying to run one of several VPN .plist files that were not removed properly from /Library/LaunchAgents, and that causes the laptop to hang unless I boot into Safe Mode and bypass all that. It's too bad these are not automatically disabled as part of the upgrade process so the customer can later reenable them as needed.
For some reason, Safe Mode is not accepting my administrator password, so disabling these login apps from Settings or removing them from the filesystem is not possible. However, if I could downgrade to Sequoia 15.0 by booting off USB, then I can boot normally, then disable them as myself - but creating the installer image requires either another Intel Mac or an administrator account and I don't have either.
It's a little frustrating that creating a bootable USB drive requires administrator privileges, as this only stops people who don't have another laptop handy.
Any suggestions here? I feel like I've tried the usual keyboard boot keys, like Repair mode, Diagnostics, and Clearing Memory. I am sure the hardware is fine and the filesystem is clean.
MacBook Pro 16″, macOS 15.1