If you put it that way, I have to say yes. If the person meets all the criteria, why does the process stall at that stage?
If I may, I would like to make a few comments on training.
I would urge you to include people who have mental health problems. To my mind, it is essential for the professionals being trained to hear what they have to say.
Getting back to your question, I would say the following. It is indeed discrimination. On what basis is the person refused? Is it solely on the basis that the person has a mental health disorder? If that is the case, it is stigmatization if not discrimination.