If you can provide proof of purchase with your name and ID, the Apple store will be able to assist you. Otherwise, you are out of luck.
yes. apple genius bar can help in this case, if s/he has proof of purchase.
i needed this exact kind of support a few weeks ago.
i forgot (yes, i know...) the Firmware password that i had set.
and i too wanted to wipe my Catalina buggy disk completely clean and restart but i couldn't do it because of course it needed to know my firmware password.
luckily i was able to get my proof of purchase by simply logging into apple web store which is how i bought it, and seeing if the purchase was still in there, and it was.
apple nullified my firmware password.
(the problem then became that IF you set a Firmware password then remove it, you loose all access to Wallet. it doesn't like it at all any attempt to remove a firmware password if after you have a Wallet set up while a firmware password was in place. so to regain Wallet functions, i needed to set a firmware password (this time i wrote it down...). it then happily allowed me to set up credit and apple functions.
but i am confused about the term "Activation Lock".
i know i have seen that phrase but i cant remember the context.
is Activation Lock set overtly by your choice using yr apple ID (so that yr apple ID can be used to unlock yr mac)?
also, while I'm at it: Recovery Key for a mac. (this Recovery Key is mentioned in the iCloud preference panel's Password & Security pane's Recovery Key section.
So this Recovery Key is used if you set it and you want to change yr mac log on password, correct? (meaning, you need a 2nd verified device in order to change yr mac logon password, correct?
And: is the above Recovery Key the same Recovery Key that is also mentioned in Security and Privacy preference panel's File Vault pane?