A lack of replies does not mean people are being nasty. It means they have nothing to say at the moment.
When I made an appointment, I mentioned it was largely to pinpoint what was wrong with me, and I mentioned the possible ASD to the secretary. There is a standardized method of diagnosing ASDs which the psychologists are supposed to use. You can discuss it with your psych when you go in (keep in mind, not all psychs are even able to evaluate/diagnose ASDs!), but if she is not prepared to give you those interviews then, the likelihood of you getting any definitive answers from that session will be slim. Perhaps call the clinic and ask if the therapist is qualified to make the diagnosis, and express interest in discussing the possibility before your meeting. It might just speed things up a bit.