We do not know the precise failure of the 332L2 epicyclic gearing but I have concerns about Sikorsky using titanium studs on a vital part of the MGB oil system, why change from the usual steel studs used for years? Titanium is not very tolerant, the MRH on the Lynx has to be treated with extreme caution, any slip of a spanner causing a ding on the material is a big problem. I suspect that titanium might be similar to stainless steel (SS) in day to day use, we had to be very careful when using SS bolts not to strip the threads and sometimes it couldn't be helped.
With a filter cover that had to opened several times during the tbo of a S92 mgb perhaps the studs were inadvertantly overstressed causing an ultimate failure. We really need to know why the studs failed on the NL S92.