The IAA can only endorse Ryanairs procedures and as they stated they are "on a par with the safest airlines in Europe", the problem is that they can really have no idea how those procedures are implemented or abused unless issues are brought to their attention either by Ryanair as a company or the individual themselves. The truth is that many of the employees would not want to do anything that brings them into any conflict with the management if there was any way to avoid it.
Employees who had any sort of concerns would see the options as,
1. Report it using RYR official channels (possible career suicide, especially if your a contractor)
2. Report directly to IAA (possible career suicide, especially if your a contractor)
3. Say nothing, stay off the radar, hope nothing comes of it or someone else reports it.