Here is a YouTube video with the steps to follow to delete your TurboTax account.
https://www.youtube.com/watch?v=VOXp4SXK8ac
It appears as if following the instructions in that video only deletes data, not the actual account.
You are probably correct. I believe to actually delete the account a request has to be sent to TurboTax security and it takes about three months for it to be processed. I thought that this video was a work-arround that but did not try to delete an account with it.