Further to NickA's wisdom 
The Chinese "shop" opposite is a BB dump so if you really want to chance it beware.
Have enquired at the "legit" Thai along the way also and the call taker is very snippy about being asked which "ladies" are working and will insist they are professional masseuses. At the elevated price I haven't bothered trying even to find a decent masseuse there as have enough tried and test options for less with good attitudes and decent extras assured and all away from Croydon and it's ropey punting.
I think by and large the "legit" Thai further along has always been legit barring the odd episode.
Around 2015/16 there were two Thai masseuses working there. One was called April, who was 100 per cent legit, stocky and glum-faced and uncommunicative, and basically beat the shit out of me. Great for getting rid of knots, but I'd have been reluctant to let her touch my penis in case she tore it off.
The other was Jeana, who was extremely attractive, a good laugh and often quite flirtatious. Her massage was also first rate, and she'd get the en-suite shower running for you and wasn't fazed by seeing you naked. On more than one occasion I was erect in front of her. BUT nothing more was ever offered and I found her massages so good and therapeutic I didn't want to jeopardise that. In hindsight, perhaps I
should have chanced it. I'm normally more bold. But I have always wandered if others got lucky. She moved on and runs a very legit shop elsewhere now…
Any further intel welcome.