I know it's easy for me to say but I would have flat out demanded some money back and not budged. I've only done this once, and yup, with an asian girl. I just said that I asked about certain services beforehand, that were included in the price, and they were agreed, but were either not on offer or cost extra. I asked for half back. She dithered to and fro because I wasn't leaving. I just got dressed and casually repeated myself.
One trick that helped was that I got my phone out and pretended to start texting, but I was just setting my alarm to go off in a minute or two's time. I then 'answered' the call calmly and said something like "yes I'm still here." "small problem, I won't be long," etc. Just acted totally calm and in control until she phoned her pimp and handed the phone over to me, then I explained and got refunded some of the money.
As a rule from then on I've tried to avoid asian escorts, only making exceptions with good reviews here, and/or credible AW feedback, and even then one had a similarly shit situation. Anyway, there's no way I'd go to a crap-hole address now, and even in the nice apartments I'd assume I'm going to walk.
Sorry for the rant, but it's always bad reading these reviews after all these years. On the plus side, much appreciated that you left a review to highlight it. Better luck next time.