Wonderful that all survived with seemingly few injuries. Congrats to the pilot. 3000fpm descent?? And as mentioned presumably no seatbelts? Do parachutists think they are Lady Diana?
This a/c had a complete power loss in 2009:
https://www.atsb.gov.au/publications...ir/ao-2010-005, report says:
"compressor turbine blades that had been installed in the engine during the most recent overhaul were not approved for the PT6A-114"
17 POB? Seems a lot, but what could possibly go wrong?