There's a whole timeline here. You and others are citing disparate things that happened over different times and in reaction to different things as if they are all related in a linear manner.
The original statement by United was very early in the process. you and I don't know what info they had at that point. The "firing" came later, ostensibly after more info was received. The fact that they no longer want this woman to serve on their flights corroborates the alleged victim's story. It does not confirm it, but it corroborates it. I don't know why whatever third party who hired her still retains her at this point. It could be because they believe her version. It could be because they believed a hybrid version which is still not bad enough to fire her in their minds. It could be because they leave it up to the various airlines to decide whether to use her or not.
What we have for the other story are quasi-anonymous posts. One of them on, apparently, a Pakistani website. The other on the what appears to be a blog/trip advior-esque site. We have this allusion to the "no one ever gets a whole can of coke" which in my experience, and given I've probably flown in two separate military assignments as a defense attorney and a trainer probably 50-60 times in the last ten years, is categorically not a policy, or certainly not one that is perfectly followed, because I know for a fact I've been given a whole can before...I've also been given just the plastic cup. More the latter than the former, but it's happened (and no, I wasn't in uniform).
There is nothing White Knight about disagreeing with jumping to conclusions, which is what you and others are doing, and what I've said which even makes allowances for the possibility that she is lying.