Er, yeah that's a LOT of trust in Interlining your baggage all the way home - LOL
Well if you did do it and they don't arrive in NQY then the EI handling agents lost luggage desk at NQY has to create a PIR and give you a lost luggage ref.
Then you have to call your Travel Insurance when you get home within 7 days to report the loss.....But chances are you will get the bags delivered to your home within a few days, or worst case is one or more bags is lost for evermore...
I actually just tried to call NQY Airport and HM Border Force there to ask about your 'Clearance' scenario - but sadly no one could give me an answer, just went around in circles, not even Border Force as there are no flights in at the mo.
I find this incredulous they do not know the answers as both NQY and EXT airports are bannering adverts to use the new EI DUB flights to connect with the 'New World' -
However, there is plenty of clear info about the Outward U.S. pre-clearance at DUB but nothing about returning to the UK via DUB and how one has to do it....
I'll keep digging....