Just a couple of thoughts.
Assuming reasonable weather everywhere, and an engine stopping in the cruise at say FL350 overhead the MCT.
If the other engine were to stop, where would you rather be,65nm from both Man and Dub at say 20000ft or overhead Manchester(I know,go to Valley but the same principle applies halfway between Valley and Dublin at 10000ft).
As the QRH says 'land at the nearest suitable airport' for both fire and straightforward engine failure,would you continue to Dublin with a fire?
If I (as a pilot) were a passenger in that situation I would rather go to Manchester.I know, I am a coward!!
You can try and baffle everyone with 'science' but I agree with Black Dog, who last time I saw him was a jet airline Captain!
The interesting question to me is not where they went,but why?