Yes, which OTA's are shown depends on the location. When I change the location dropdown at the bottom of the screen to UK, the lower OTA price is shown.
Unfortunately, I need VS for the SAS promotion, I don't think you can route on them. You can, however buy a DL-operated ticket from VS (which I guess might make sense if you want to earn Skypesos?):
https://www.google.com/travel/flight...euJ7KhwwmayUo8
Oh, and I forgot to mention, the lowest fares ex MEX seem to have a 28-day advance purchase requirement.
Considering that travel also has to be completed by Dec 14, it's a rather small booking window.