Given it was the early hours of the morning, I doubt if either flybe or bmi would have had anyone on station with the authority to accept these passengers at a reduced fare as a goodwill/
PR gesture. Plus we do get an awful lot of sob stories to deal with, and it becomes difficult to tell the genuine ones from those who are pulling a fast one. The ticket desk staff were probably busy dealing with other delayed Ryanair passengers who were fortunate enough to have the money to buy new tickets when they saw their own flight was delayed, and would not have had the time to start phoning around to try and help these people.
Ryanair do not employ customer service staff at airports. Thats partly how they keep their fares low. They use handling agents, who can face harsh penalties if they do not obey FR rules. That is one of the things you must accept when you book with MOL. Customer service is another one of the many things not included in the price of the ticket!
No doubt BMI/flybe missed the chance of some good
PR here, but I have to agree with the posters who suggest flying the night before may have be prudent for such a long and special day, and who suggest using a "full service" carrier would have been a better option, particularly when it came to transferring tickets from one airline to the other.