Repotting Lc. Mari's Song difficulties

[Jenn4a]

Both Mari's are on death's doorstep.
The divisions from the smallest plant might have the best chance of survival.
Both plants were divided by rotting in the rhizome and roots. I've updated my threads about the Mari's; I'm sorry for repeating the info.

-old-
I repotted the Biggest Mari's Song tonight but think something might have gone wrong

I was clipping dead roots, and it seems like the rhizome was already split before I unpotted it.
it was rotted;I was new and didn't know for sure.

When I first got it I noticed that the two newest growths looked black around the center, as well as the roots peeking out . I didn't think much of it, and I couldn't tell how far down it went.
Well while I was repotting I noticed that most of the new growth's roots were black and hollow or mushy.
NOTE: I should have cut off the smallest growth to check how far the black went through the rhizome
I did not try pulling them further apart since it looks like further down that they are still connected by a single small root. The tangled roots at the middle and bottom kept them together basically. I realized that healthy Cattleyas don't pull apart this easily and should have expected rotting as a culprit. Also, if the rhizome isn't connecting the pseudobulbs, the plant has been divided.
It seems to be separated with 3 back bulbs, and the newest group looks to be 4. Now it's 3 and 3.

I can't really tell if they're actually still connected or not, and it looked like I might lose the smallest growth anyways. I think the smallest might be lost to rot. A couple roots were rotted all the way up.. even to the newest growth. I SHOULD HAVE listened to my instincts and cut it off.

Should I be concerned for the overall plant?
Is there something I should do, or is it just a waiting game to see what damage has been done?
the plant could be in better health if I wasn't so gentle with the rotted areas.


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sorry if I added this in the wrong area!