I can't provide insight for that row specifically, but keep in mind there are a few slight variations in the different versions of the A380, so the onboard tour might not be 100% accurate. That being said the EK staff may be confused as it is a window seat, as in an A or K seat, and they may not have insight into whether or not it is in fact a seat with an actual window.

AFAIK there is one flight from LGW which is in fact a 2-class aircraft. The A380 wing is enormous so a lot of seats have a blocked view because of it, best bet to get a view out the window is upper deck, not sure what extra legroom seats are available there, though I'd imagine the first row would be extra leg room, and probably also have a window. I've been in the 2nd row on the upper deck but in the center aisle and can't recall if the first row had a window.