Majorski was a church member, but it seems he left some time ago (see EDIT). His last dealings with the church on public record involved a law-suit against UCLA lecturer Dr. Louis J. West in 1993. He does not appear to have been well for some time - what led him to illness is too open to conjecture, certainly at this stage. Should a clearer picture of Majorski arise when the official ruling on the shooting is made later this week, I'll post again.
EDIT - Apparently Majorski was a practicing member of the Church as late as June 2004:
Tommy and or OSA Int intentionally omitted from consideration the fact that ASHO's Auditor Mag of June 2004 lists Mario Majorski amongst the people intending to come next for the Saint Hill Special Briefing Course training.
I hope to confirm this soon.