The a member of staff will review all submissions to ensure they are correct.
- Does the public key match the one sent in the memo
- Is the key a valid key
- Does the key differ from the one we have already associated with the account
If these three things are true we can be sure that the key provided is new, owned by the right person and will work as long as the owner has the corresponding private key.
I hope this clears things up for you.