If they go to Dover, it’s possible that they go there first and by boat crossing the English Channel, there’s ferry service from Normandie region in France like Canais. That may explain lack of sighting at airport.
I was in London last week, Tyler/Korey were at the corner of Regent Street and Piccadilly. I got a picture of the same street corner.
Edited to add the picture I took last week, they should be at that corner behind this statue.
