Blaxmax,
Let me clarify. The experimental sticker on the 44 means I cannot fly it as a commercial helicopter, so no fare paying passengers or mustering. The stickers do not bypass any CASA regulations, in fact it has tighter ones hence the stickers. No ADs ignored.
I cannot speak for TET regarding crash investigations under 5700kgs. But there is anecdotal evidence of previous mustering crashes which haven't had the 'full' investigation if it's just the pilot concerned.
Cheers FP