Sorry- but your story doen't quite make sense. You say that it was the same plane going on to dublin. iF this was the case, wityh only half an hour between flights, your sister would NOT have had to get off the iarcraft in the first place. Seems more like the tickts she bought are 2 single tickets, meaning that you have to re- checkin at Derry. Therfore, bags would come off and have to be rechecked in - in a similar way to LCC's. Logan air, are in NO WAY a sh*tty carrier, and I think that your sister is to blame, as all due repect, all othe passengers managed to make it to the flight on time!!!
Its not every day you get a terrorist attack on your airport or place of work, and the textbook training does not necessarily mean it will fit in with real life sitiuations. Sp please spare a thought for the poor agents in the terminal who had the nightmare of reacommodating all the previous days pax, as well as the new days pax. You just have to be patient i'm afraid. shouting and screaming does not help in any way. Why didn't you get a direct flight to dublin?? there are hindreds of direct flight s to dublin from GLA, EDI, and PIK