RTN or hopefully something else HELP

[bling_bling466]

Well I picked up a nice tabling acro and it looked good for 2 weeks then this morning I noticed a little tissue loss. Then got home from work and noticed more the half gone. So I removed it and got a couple nice frag witch are now on the frag tray I wasn't able to get pics because I tossed it lol. The question is when I picked up the coral he cut the colony in half throw some water in and gave it to me. I'm kinda new to sps and was wondering if this is just stress or related to how he fragged it. Would it still be RTN and is it contagious. If so what are my next steps