Hi, I am not a MAX and neither a VRAY user.
But, it looks like that there are two things happening:
A non ACES gamma 2.2 view transform looks simply different to the ACES RRT&ODT or any other view transform.
The 3D-scene RGB value of 1 is mapped to 0.81198 in the sRGB ODT. I wrote a bit about this topic on my blog (1.2. Linear Ramps – Brylka – TooDee – PanicPost)
Blender for example does not convert picked color values from sRGB to ACEScg. You have to do this by yourself. Otherwise you might end up with too saturated colours. I linked another article from my blog directly here on ACESCentral.com (Understanding Gamut with ACES & Blender)
I hope this helps.