Nepenthes quickly turning black

[adnedarn]

Hello everyone, looking for some advice since I've not experienced this before without a heater or cooler going down and extreme temps setting in.
My N. 'Simon' was doing fine and looked good 8/25 (1st pic) and now it is mostly black. It is somewhat new to me (June) but definitely was growing and pitchering. I've not completely unpotted it but did give a nice tug to see if the roots were gone, it seems to be well attached.
Thanks!

 

[Grey Moss]

Hey Andrew, when I see rapidly advancing black and die off its usually due to stress. Even without extreme heat a plant sitting on the upper end of whats acceptable seems to make it vulnerable to a sudden collapse over enough time.

 

[adnedarn]

Interesting that it would pick about a week after the night drops started getting down near where they were for the person I got the plant from to start showing it wasn't happy. Maybe it'll be able to recover then. Thanks for the observation!

 

[hcarlton]

That it appears to be blackening from the stem outwards and bottom up suggests there may have already been some stem rot issues to start with (potentially pathogenic), and any recent stresses accelerated it. It may have had roots, and the roots died but are still attached to the soil so feel like they're okay but are already failed.

 

[adnedarn]

Rot is what I was leaning toward. I treated with something I've not used before for " virucide, fungicide and algaecide". Last ditch effort...