Diane said it much better and with full perspective, regardless anything else I've said, I again extend my deepest sympathies to friends and family.
With regard to whether or not there is a current at Mexico Rocks, I must disagree. Certainly it is not that of Hol Chan, but still exists.
I'm a diver, occasional snorkler and long time swimmer, super comfy in the water. My last time out snorkelling at Mexico Rocks, I was so comfy that I was pulled out over the staghorn coral, before I realized it. I had one heck of a time getting away from it without damaging either the coral or myself. (note, at that time the coral reached almost to the surface of the water)
Someone less comfortable in the water, would likely have made a helluva mess of both the coral and themselves.