I had never heard of this either. I googled "communication room" plus "autism", and only got 41 hits. One place described it as a sensory room, another place described it as their speech pathology room. A third place described it as a play room where the staff observes the children's speech and actions during play and uses them to evaluate and plan future sessions.
Since it's clearly not a widely used term, and the definitions seem to vary, you don't have to feel like you're asking a "stupid question" when you approach them for more information on this.
Good luck with everything.
It's ironic that you are saying this, because I just had to take my dd for a speech evaluation. Her language is very good, but it's her articulation that are drawing the red flags for her.
The SLP that saw my dd said that she thought Jozlyn might benefit from a social communication group. I asked her what this was and she said it's a class 4 x week, that she would attend. There would be 20 minutes of pull-out 1 on 1 ST 2 x week. She explained that it's a lot like regular preschool but they focus a lot on verbal things. Large group games that require a lot of speech, singing etc. They are supposed to make it mostly communication and as interactive as possible.
This might be a little different than what you are being told about though, just because for my dd it is a 'preschool' type thing. I had not heard of it until now...Mason was in the special needs preschool class which is different, but the SLP said she didn't think that would be the right setting for Jozlyn because really it's only her articulation that is a problem. Her cognitive is right where it should be.
Hope this helps some.
My daughter's summer tutor told me they have communication rooms for kids with forms of autism at a few of the schools. She said I should ask to put J in one. Social communication room? Has anyone heard of a social communication room?