Walk in shower area. - Tile Advice

[Etherglide]

Looking for a bit of moral support here. Asked by a plumber, who Ive done a number of jobs with, to tile a large complicated shower room/bathroom area. Usually not a problem but Ive turned up at the job today, they've left the original shower tray in, then laid ply up to and over the height of the tray. Ive then been expected to overboard the ply with 6mm Hardiebacker board, lay a heating mat and then self level it. It wasn't tanked but had some Mapei tape loosely brushed onto the joint between the tray and the ply. Ive seen the job and immediately brought up my concerns, thought about it for 30 seconds. then announced that I can't accept that as a starting point from a tiling point of view. I tried calling the plumber but he won't answer my calls so Ive had to text him. After 4 hours Ive still had no reply. I just need someone to tell me Ive done the right thing. I should have taken pictures but I didn't. Im going to lose a lot of work and my partner is concerned.

 

[Dave]

Run for the hills. A disaster waiting to happen

 

[Perfect Tiling]

As above....keep away from it. If the plumber ain't answering then he knows there's an issue. I would rather have no work on badly prepared jobs than have later issues bite me that may cause a bad name for my business or legal action that I can't afford....it's better to sleep easy than wake up every hour worrying....