I'm really sorry for what is happening. I too find it very strange that a psychologist would allow the mother present during these questions. A few months after I separated I requested that my children be evaluated, not for court purposes, but for my own peace of mind and to find out if they were more affected by my separation than I might think. My children were at the time only 3 years old and didn't speak very clearly yet. Nevertheless, I was not present when the psychologist spoke and played with them.
It seems very strange that your wife was allowed to be present. It would be interesting to see what that psychologist's curriculum is like. Just as in all other professions, there are good psychologists and not so good psychologists. If I were you, I would certainly look into this.
Try to stay strong, Tim, for your children and for yourself.
If I can help you in any way, you know how to reach me.