Your thread has been moved out of Help and into a more appropriate forum since this is more of a complaint.

That said, if you suspect someone has multiple accounts, you can file a support ticket to alert staff.

The only times that pet names are made available are when accounts are inactive for at least 12 months, and you will see that the name is available on the pet's page. The same is true of user names - they are available once an account is inactive for at least 12 months.