I would "love" to read the terms and conditions of these TT products to understand what could and could not be shared. For all we know, those T&C's did not permit TT or Greendot to share the permanent account numbers with the IRS
Greendot and SBTPG are affiliated companies / sister companies. For SBTPG to share information, such as that temporary account number may have required an affiliate agreement that the customer would have to sign off on in this unexpected situation. There are severe banking requirements about sharing information between bank and non-bank affiliates without additional customer consent.
I simply do not believe it is as simple as the IRS jumping into the deep end of an empty pool. It may have been SBTPG, Greendot and TT had already jumped into that deep end of an empty pool and the IRS had no choice but to follow.
