First, we need to know about what he testified.   Then we can discuss that in the context of his qualifications.  Otherwise, we are going in circles.  If, as Negrete claimed, he testified about psychiatry, then his lack of passing the psychiatry boards would be relevant.  Otherwise, it really isn't.  Also, I noted on Tim Bolan's website that Barrett shouldn't even be called "Doctor" because he is no longer licensed.  That is absurd.  Once he has an M.D. degree he can forever call himself Doctor if he so chooses.  The status of his license has nothing to do with it - even if he had had it revoked, which does not appear to be the case.