WEll thats up to you,but Ronnie told me to do the same thing one one of my corals and it works,cut right above the effected area and glue it to a plug,then see if that will fix the issue,Ill let him give more of a hand on it than me,he is 10x better at SPS than me.
very well might be, hard to tell from the picture.. If i were you i'd do a once over on all your corals to make sure tho.. those things are sneaky little suckers.
looks like you have pest issues and stability issues also. I would start going with the standard two part dosing, b-ionic, brs two part, kent two part, this will help with your PH issues.
get yourselve a bottle of revive and dip the corals and see what comes off.
I don't see any red bugs - I'd stay away from dipping any of these stressed out corals unless you want to see what color the skeleton is (white - yep, I spoiled the surprise).
They are stressed as is. A month or two (even if you DO have RB) won't finish anything off. Let things settle and get your Alk and Ca stable first before being too active.
Nothing good happens quickly in this hobby. Now is the time to analyze why. In a week or two (or a month or two) will be the time to fix the why.