This isn't even new news: Tether changed their terms last year, and admitted/claimed to the NY Attorney General that they only have 74% cash last year.

https://cointelegraph.com/news/changes-to-tethers-terms-of-r...

https://bitcoinmagazine.com/articles/holders-are-not-at-risk...

Note that all of this is over a year before the Tether printer kicked into overdrive around April this year and started inflating from $4B to the current $18B+.