Do I still have to do that?
Yes, otherwise you can't prove that this account isn't stolen. You won't be able to recover it the future as well.
The multi-sig address I previously posted starting at 3 in 2016 came from a custodial wallet so I was not able to sign it.
So, why did you stake it?
And the one that starts with 1 from blockchain.info or .com as far as I remember, I haven't used it for a long time and I've lost access because I haven't held its private key since my old laptop was damaged and I was unable to recover.
Isn't it a great coincidence that you can't sign from both addresses? Anyway, you know what they say; not your keys, not your coins, not your identity.