Need urgent help with Grohtherm 3000 thermo fittings

Hi guys
I need some urgent help. I have my plumber here trying to fit a Grotherm 3000 thermo valve, and i need it to divert to the tub. I am using a hand shower with a wall union only.

The internet site i got the fittings from told me that i needed a diverter spout and a twin ell. But when the plumber read the instructions for the valve, it says that this one (34126) needs another stop valve and trim!

Does anyone have any knowledge of this - my plumber can get the stop valve, i just want to confirm what he is doing!

Thanks for any help.

You are right that valve needs a diverter spout and a twin elbow.

Thanks for the reply.