Henley and Burbage were both pulling a lot of g trying to evade that question. One clue is that Burbage's comment about "codings" should almost certainly read "coatings". In fact there are three layers, as it were, to reduced radar cross section - shaping (which everyone accepts is the same for all versions, no news there) edge construction (leading and trailing edges and inlet lips) and surface treatments.
It's pretty clear from this evidence that the non-UK export model will be different from the US model. What's not clear is whether the US and UK models will be the same in terms of edges and coatings: the aircraft that rolls off the line may be identical, but it may not be the same once it is painted or if it gets some new edges added.
The "meet the same requirement" line is also subject to interpretation. It's entirely possible that the UK aircraft meets the requirement but that the US aircraft (or some of the US aircraft) exceeds it.