I am always willing to impart knowledge.
A T:E (testosterone : epitestosterone) test determines whether or not a person is using synthetic hormones. The average person has a 1:1 ratio. Most AC's use a 4:1 ratio, as almost everyone falls into this range. The NSAC used a 6:1 ratio, 95-99% of all people are naturally 6:1 or lower, so a false positive is extremely rare. If you are above 6:1 (or 4:1 in some places) then it is inferred you are using synthetic hormones. Your actual testosterone levels are NOT able to be determined with this test. There is not even a correlation. Someone with a 50:1 ratio could have low testosterone.
Someone using TRT necessarily is using synthetic hormones. That means their T:E ratio will ALWAYS be above the 6:1 ratio of a normal person. That means anyone using TRT is given the more expensive test to determine actual testosterone levels. That is why Chael being 16.9:1 would not have resulted in a suspension, because his actual T level was not tested, and there is ZERO evidence his actual T levels were high.
Now for Vitor, he was tested positive for steroid abuse early in his career. That means he should NEVER have been using TRT with a TUE as steroid abuse can cause low T. This also means the last random test he was given and failed was a T level check, which was high. That means he was not using TRT to achieve normalcy, he was using TRT as a mask to abuse steroids. It's basically one of the most disgusting cases of steroid abuse in MMA, and is what resulted in TRT being banned.
Is that clear? I will clarify anything you don't understand.