Sometimes the girls just have a bad day like the rest of us. It does not excuse it, but may explain it. Always good to say something to the mamasan when leaving. A good one will give an "attitude adjustment" to the girl, or if a constant problem, replace her.
I should have said something, but I think the other girls who saw our cold interaction while I was getting dressed knew and I stared at the dude manning the desk so I think he knew, as my look made Ding Ding nervous and bow as I left. She knows and the ones who saw our interaction know I was dissatisfied.
That said, you are right that I do not know for a fact why she performed the way she did. I do know the inconsistencies in her answers to my questions. I should have said something to MMS, but I also did not want to mess it up for those who received good service from her, particular the person who referred me to her. Hence my YMMV notation.
I do wonder if she was upset because I asked for Mônica first, who left for Colorado/Nevada, then asked for Ding Ding second. Whatever the case, it is what it is. ✌