If there are, indeed, other TurboTax customers who have received their second stimulus deposits already, then they would likely be those whose filing fees were not deducted from their Federal returns by way of TurboTax's fee processor, Santa Barbara TPG.
This would mean that the IRS has only one recorded method of direct deposit on file for those individuals, which is their own personal bank account; therefore, the chance of a mix-up is quite small and their payments are sent directly to that one account the IRS has a record of. On the other hand, for those who opted to have their filing fees deducted from their Federal returns, the IRS has two sets of direct deposit information on file: Your personal bank account as well as Santa Barbara TPG's account, which is where TurboTax has its filing fees processed.
Since tax season had long been over, TurboTax closed those fee-processing accounts and the IRS sent customers' payments there in error. This is where the mix-up occurred and it's why some people who used TurboTax may have successfully received their stimulus payments while others have not.
The first stimulus payments were not routed through TurboTax's fee processor - they were sent directly to customers' accounts from the IRS (you can see this information in your deposit transaction details). Why this mistake happened the second time around is a mystery.
