In reality you never fail a check on one item. It may be that the examiner saw a number of things which failed to come up to the required standard.
When I was taught to be an examiner (by CAFU many moons ago!) I was told that if you had to fail anyone (formally) pick something which cannot be argued with! E.g. going below minima. In the subsequent debrief you can then mention any further items.
At the end of the day it's all a question of is the examiner happy to sign your rating? If he/she is not happy to do same he/she has to find a cast iron reason. Its a while since I did any examining but the formal fail paperwork has to show reason(s) for failure.
Believe it or not examiners do not want to fail candidates for test! Remember their authority does not come from the company but the relevant licensing authority (CAA).
Finally you can complain about the conduct of the test but not the result!