Usdt is a company that has been dragged for a long time, even before Certik was founded. They've been charged and investigated in the past for not being transparent with the equivalent pegged fiat deposit for each USDT and bitcoin price manipulation. With USDT as centralized stable coin, they can freeze your money any time especially when they don't find you transparent. (According to their ways)
https://www.certik.com/company/disclaimer
Just a friendly disclaimer, you should check.