The white plague is not new. This is an old story resurfacing. I snorkeled off St. John two years ago with a NPS researcher writing a dissertation on the die-off of Caribbean brain and boulder corals. The pillar corals were still doing fine as were the soft corals all over the island. That is, except where the hurricane damage had covered parts of the reef in silt from hillside run-off. But those were already coming back.
The question is whether the plague (a disease, bacterial IIRC) is made worse -- bacterial spread faster -- in the warm water. That was the subject of her study. It's an open question.
The worse story is the Great Barrier Reef, which has suffered mass die-off in the last six months documented to have been caused by high temperatures. Of that there is no basis for dispute. You can close your eyes to global warming if you wish, why you would do so based on all the evidence I have no idea, but you can't dispute that the GBR death is from high temps (sustained several weeks over 89deg at one stage on a large stretch of the reef that died).