Phalenopsis - dying roots with green, growing tips, multiple keikis keikis

[Archades]

I have a Phal orchid that I had put keiki paste on a few months ago. Repotted it into a clear container with quincan rock with a small amount of an "orchid bark mix" from Bunnings and a few bits of perlite. Tried to make it a loose and high airflow mix to prevent rotting in the first place...

My climate is the wet tropics, usually in a high rainfall area of 4-5M per year. Far North Queensland, Innisfail area (cyclone magnet). The recent year has been a hell of a lot drier though. Recent weather was very hot in the last fortnight, 35+ celcius with high humidity. It is a bit cooler this week but still fairly hot.

All of my orchids are on the patio, never get direct sunlight but there is a lot of indirect light from light/near white paver/tiled area. I was watering them every 4-7 days, I usually wait until I don't see any humidity on the plastic container and the rocks look dry. The roots on all of them are usually green or silvery green, they get quite a lot of airflow, most of the leaves are thick, plump, firm, n lime-green/what I usually see on orchids. For the last week n a half whilst the extreme heat was around I was watering them about every 2-3 days.

About a month ago I noticed a keiki growing finally, or at least I believe it is a keiki. Today I noticed 2 more growing but I saw the crown and roots and they were not happy! The roots were nice n green every time I've looked at them so I am pretty shocked by this. Could too much hormone cause this kind of damage or is it too much water? I've sprayed it with Triforine as soon as I saw this.

The black starts around the crown and goes to about 1/3rd of the root, the rest of the root looks perfectly healthy and is putting on multiple offshoots and growing nicely so I have no idea what is going on. The lil mini string inside the roots was green under the black/rotted outer bit and there was one part of the string that was black/yellow. I can see at least 1 green root still attached and I am hoping that stays green! The leaves still look healthy to me?

What can I do to save this orchid. I've read Seasol has auxins to promote root growth, should I apply that now? I have wiped off as much keiki growth paste as I can as I've read that stuff limits root growth.

I've also read there is a keiki paste specifically for root development, these keiki's have no roots so would that be worth getting?