Hi and sorry for the slow reply,
Geoff is correct all taps and flushing units are (or should be)operated during an inspection. This is to test for several things, including; water flow (sometimes the pipes aren't even connected), pipe hammer (as this can cause leaks in walls), you look at the drains to see if they are clear and draining well, inspect 's' bends and connections for leaks and if concealed (as in a 2nd storey wet area) carefull inspection for evidence of past/ current water damage from leaks.
So based on your info I think your inspector omitted to inspect/test the area which is why s/he should have professional indemnity insurance.
Have a look at the Australian Standard for property inspections - residential and then see if the report claims to comply with it.