Just based on the photo I would also say right side is probably to far gone to save.
How long has it been in your tank?
How long has tour tank been set up?
What are your current water parameters: alk, cal, mag, no3, po4, temp, salinity. (You should have no ammonia or nitrite but if you do your cycle may not be complete)
What’s your lighting and flow like?
All of the above will play a part in a plan to save this or avoid the same issue with other corals moving forward.
if you have another stable tank or a friends tank: my next move would be a idodine dip and move it to a stable system- and hope for the best. the left side may bounce back but I think not so good odds.
maybe someone local to you would hold it in there system to see if it recovers or not. I would hold it for you but I think your far away.
these are generally pretty hardy in mature and stable tanks- but hate major swings in parameters as well as any toxic and like copper or iron from rust or even stray voltage. I’ve seen them go fast from these things.
Good luck. Keep us posted.