why would the pilot be familiar ? Are you familiar with every part of a helicopter I think not. One has to assume that if engine was fitted by an approved organisation that it must have been done properly. In EASA land this would be picked up on the audits we have to do on ones maintenance company and if not by us then the audits carried out by the regulatory body.
Doesn't mean though the company was trying to pull a flanker, engine should at the very least had a shock load inspection