Thanks for reporting this. Romullus asked me to look into this.
I understand the issue. You would like to have 6 different objects (or more) and each of those 6 objects would receive environment overrides randomly based on the multimap plugged into the refl/refr overrides. Is that correct?
The information I need is how such workflow can be used in practice? What is the use case, for example in an archviz scene?