To me, this is clear evidence that only that right side was intended to be the “herbarium”, not the whole two part set, as some seem to think, based evidently, on the redress from “ITITNB”.
I see your point. Upon re-examination I felt it interesting to notice that the floor plan sketch I provided reveals the fountain-planter (a rec room exclusive!) in the middle of the circular room which had gone missing in TB.
Here is where it gets interesting, IMHO. The floor plan sketch was apparently created after an early draft of the script. It still features the fountain-planter but this looks odd in an area - according to the script - that's devoted to research and not to recreation.
The disappearance of the fountain-planter in the final episode may have been to tell us this is not the recreation room and/or that this is a restricted research and not R&R area.
And I’m not aware of any mirror shots in “CL”?
That would be this one, I didn't mean "flopped" (side inverted). Apparently, someone remembered that they had done that in ET to give the room extra depth by simply repositioning the actor in the opposite spot.
Both rec room scenes (ET and CL) suggest the rec room with the fountain-planter to be connected to another room with a fountain-planter (well, hopefully the other fountain would sprinkle water

Bob