You are right; if there are no data to support the argument that some members of the community are not recognized, we have nothing on which to base our claims or to set up programs and services for them. Not all problems will be solved as soon as we have that data, but it is an important tool. It's a step in the right direction; a stage along the way.
You are in a position to recommend that those questions be added to the census. It will not necessarily solve all the problems, but it is something we would like, because it could help us.