OP needs to get over it. There are, of course, people at UA more than senior enough to move specific people into F or move them up the UG list, depending on what they choose to do. Sam thing at AA and DL too.
The internal UA question is whether the senior UA person was using their authority in violation of company policy. If OP wants to report the details to UA, UA can look at it and make that determination.
But, UA -- just like others -- markets. One way to do that is to give someone in authority a "taste of the good life" (if that's what domestic F is).