Hi Sammy, welcome to the board.
If all your tank parameters are good and you acclimated the coral correctly, I'd say that with the coral dying that quickly it probably wasn't in good shape to start with.
When you say some of the skeleton, how much? Was it just around the edges or in the center? I've brought many an open brain back from the brink with occasional Iodine dips and judicious feeding. I work part time at a small shop and sometimes the corals suffer shipping stress. I had one small
red open brain that had lost almost half of the tissue on one side, but the oral disk was intact. He recovered nicely. I don't know if the tissue will regrow over that part of the exposed skeleton or if it will build a new "addition."
~Alice