Just saying - flow or light does not matter much in this particular case.
Yes, eventually he'll need to put it in higher PAR, and it does need some flow, but it isn't the cause of the problem here, it's a new coral that most likely got stressed during the move or acclimation process. If anything, a coral in this situation is better off kept under lower light than to be blasted off under high PAR.
It is advised to make sure your parameters are in check, if the is a significant issue it'll obviously affect the coral.
But from looking at the picture, I stand still with my original theory about temperature, it may also be salinity.
As for the Iodine bath, you can use either Seachem's Iodine dip with the provided instructions, or 10 drips of Lugol's iodine per 1 liter (around 40 per gallon).