https://ftalphaville.ft.com/2017/10/02/2194319/tethers-transparency-update-is-out/

There's a dead link here but I do recall seeing a PDF somewhere a couple of days ago. However it doesn't appear to be a full on flat out audit, more of a skim, but there's no way Friedman would put their name to some absolute dogshit.

As noted in the article - "…these consulting services do not constitute an audit or attestation engagement, which would include a significantly expanded scope of procedures and take substantially more time to complete."