And the cracks are starting to show - some very high quality ex-mil rear crew have chosen to move to different contracts
Another desperate attempt to snipe at Bristow! In a large outfit with various operations in various countries, is it uncommon for some people to move to different contracts? I don't know (and nor do you Crab) but I would guess it happens a lot.
Until Bristow have to cease operations for lack of rearcrew, there is no proof that what you are saying is accurate or fair. And if they do hit any manning issues, they might well choose to cover it up in the manner of a previous outfit who might have operated a UK SAR contract a few years back (off state for 'crew sickness' when in fact the engineers were on strike? RS15 declared when the aircraft had only one engine fitted?).
And even if Bristow do run out of rearcrew and admit it openly, that is hardly a worse situation than the RAF SAR Force found itself in on numerous occasions in recent years. As you yourself have stated, RAF manning of all trades - but particularly rearcrew - has been very tight for years, due to repeated failures by those in charge to recognize and address the issue, and those brave and loyal rearcrew we did have had to work even harder to make the stats look better for the hierarchy.
For the record, I whole-heartedly agree that SAR rearcrew should (in the ideal world, not the commercial one!) be remunerated much more generously than is currently the case. Preferably not at the expense of the Drivers Airframe, mind!