If irs suspects identity fraud what 3rd party are they trying to ask and will they keep turbo tax specialists informed or part of the process?

[xmasbaby0]

Nowhere in the response about your 4464C letter did it suggest that you are a victim of -- or suspected of --  identity fraud.
And as Carl says, the IRS NEVER communicates with TurboTax about your tax return.  Once your tax return has been filed and accepted, TurboTax is done and is out of the loop.  All TurboTax did is provide you with do-it-yourself tax software.  TurboTax does not intervene with the IRS for you.

[Carl]

Under no circumstances and with no exceptions will the IRS *ever* talk to anyone but the tax filer about their tax return. So there is no way for anyone but you to have even the slightest clue as to what may be going on.  The letter you received has been explained to you already in your first post at https://ttlc.intuit.com/questions/4781628