I think if you use the subscription repair tool It might be possible to move your licence to the new account. I have recently done this moving all licences of my falily from 2 accounts into the 1 subscription
the FAQ is here
But and this a big but I assume you have a new account unused but registered you may need to get into your father's account and deactivate the PC after you moved it as it a tleast the PC name seems to stay in both accounts. I assume You are using the same PC and that his account will now not be used? Re accessing the anti theft vault I am unsure of access rights support can answer this. Tough
McAfee Anti-Theft Personal Vaults are associated with the Windows user account they were created within. Specifically, the Vault is connected to the My Documents folder, which exists for each Windows user account.
Users cannot access Personal Vaults that are created by other users.
Far easier to let support do all this so call them and mention what you want to do