I suspect it's a combination of things.
Her qualifications are a little minor league on the surface but she has worked in the field for a long time and clearly has built up some competence in helping organisations build awareness and improve procedures. I suspect she has found a niche and exploited it.
I think she has been slightly hoodwinked by the WTS. I think she has been convinced to accept a WTS view of their child protection policy and has never been engaged to do a grass roots analysis. I think she has probably been swayed by opportunity to make some good cash without needing to do a lot of work. If this is true it does not reflect well on her. Her lack of preparation for the Commission add weight to this perception.
I also have a suspicion that she has went into the session with some trepidation on the basis that she probably looked at the testimony to date and realised her report and opinions would be questioned far more rigorously than expected as well as possibly becoming aware that the WTS policy was in fact far less supportable than she imagined.
I seriously doubt she will be working for the WTS again.