Presumably both people took many pictures of many waves that day, but somehow both of them decided that this is the one that is the best from that trip.
As humans we share a similar metric for beauty. I find this idea simultaneously obviously and amazing.
Open both in 2 tabs on a computer, and quickly alternate between the 2 tabs, the 3D effect is quite visible because of the perspective differential :-)
These two exposures surely overlapped, with the known photo probably exposing for tens of milliseconds on either side of the flash, but the lighthouse exposures might not have overlapped at all, yet captured a far more exact slice of time regardless.
Nevertheless, pretty cool ;)
Should two photographers quote each other's work although both are completely original?
As a point of clarity regarding the title of the article, that means they didn’t take the photo at the same moment.
What the title really means is that, the light from this instant in time hit each person camera sensor at the same moment.