My refund has not been sent by their third party SBTG. I have checked online and there are hundreds if not thousands of complaints against that company.

Actually when you chose to have your fees deducted from your federal refund you agreed to exactly that.   It told you on at least two screens that a third party bank would be involved and you had to check that you agreed to it.

Your tax refund was not sent to TurboTax.   TurboTax does not handle your refund at all.

Santa Barbara Tax Products Group, LLC  (SBTPG) is the bank that handles the Refund Processing Service when you choose to have your TurboTax fees deducted from your refund. This option also has an additional charge from the bank that processes the transaction. 

You can contact them SBTPG, toll-free, at 1-877-908-7228 or go to their secure website www.sbtpg.com 

https://ttlc.intuit.com/questions/2580357-who-provides-the-refund-processing-service

https://ttlc.intuit.com/community/refunds/help/who-provides-pay-with-my-refund/00/26410