Soil pipe too far away for Wall-hung toilet?

[NHW]

Redoing our downstairs toilet which i am pretty sure is the original from when the house was built in the 1970's. Cast iron soil pipe which is rooted through the floor and hence not something we are looking to change, as long as it does its job lol

Have a Grohe Solido Wall-hung toilet which I am looking to install but I think the soil pipe might be too far away from the back wall.

I believe the max 230mm is referring to the distance from the back wall to the soil pipe?

it seems as though the closer edge of the 'hole' in the soil pipe is 235mm away and the centre of the hole is 285mm.

Is it just 5mm off or is my calculation wayyy off and im using the wrong measurement in relation to the 230mm? also even if it was doable at 230mm does it create less stability/rigidity? In my head im just thinking that the longer something is (further away from a solid wall) the less stable it will be, especially with a full human's weight on it.

the overall room looks like :

Any advice at all would be appreciated. Thanks

 

[denso13]

The 230mm is from the wall to the front of the frame, therefore most of the existing pipe will be outside/in front of the frame, which won't work as is. It should be about 70mm from the wall to the back of the soil pipe.

You could build out the wall a bit, 150mm to 200mm, and bring the frame forward. Is there enough room for that?