Startup Security Utility Admin Permission
You have a Mac with a T2 chip, which requires an Administrator account with both a signed certificate and a SecureToken linked to that account, and the account that tries to change any of those settings in Recovery has to have the same matching SecureToken, a copy of which is held by the BridgeOS running the T2 chip.

Your IT folk have (quite rightly) locked that kind of thing away good &amp; proper. Sorry, but no coop today :)