Pictures of the gorgs in question would help, as the common names can cover a pretty broad range of corals.
The Purple Plume which got stung can probably be saved, but you'll need to cut of any of the dead stick only portions with a clean razor blade, a little bit past the dead area into some healthy tissue, and a gentle reef dip after wouldn't be a bad idea afterwards.
Pretty frequent feedings of Oyster Eggs, Phyto, and for some gorgs, cyclopeeze/brine/etc, as well as good strong but indirect water flow are very benificial.