The problem with this line of argument is that it requires us to assess how much commercial intelligence RYR want us to display. I do not know the answer to that question, but I suspect that given we are all assimilated Borg-like into the airline, "not-much" would probably cover it.
In my experience, the handling agents are generally good at answering radio calls. If the crew called them, the agents could then call Dublin and get an answer for them in advance of the approach. I have no idea if this happened. Crews should take 'reasonable' steps to protect their positions.
Trying to argue that the cost and inconvenience of a coach journey, plus an a/c out of base for first wave the next day (cost unknown to the flight crew), versus a fine for an after-curfew landing (cost unknown to the flight crew) would be a difficult position defend in any subsequent meeting.