And I think the word "dodgy" is an overstatement.
It's the way GAA went about doing things which I disagree with, not the actual assessment being conducted by OAA. I understand that GAA never promised debriefings or refunds but that doesn't mean it was the right thing to do - but hey, it's Bahrain so 'mafee mushkilla'
Technically speaking, OAA is responsible for selection with only some help from GAA.
OAA can whittle down the numbers by their selection process and 'green light' a group of individuals who would probably make good candidates, but GAA can still pull the plug on any number of those candidates based on their own criteria.
Remember that OAA is regarded as the best FTO in this sort of business, and surely they don't want to hurt this eminent position by accepting cadets who are below their well-defined standards.
Your quite right. OAA is a well oiled pilot factory and they've really streamlined their flight training operations. There's little room for them to allocate resources for those who fall behind and need extra work.
Don't forget that in the UK, it's the UK CAA that externally examine students when it comes to your Class 1 medical, your ATPL theoretical exams, and finally your Instrument Rating skills test - your examiner will have been appointed by the Authority and not the FTO in question.