My Orchid is...Pregnant?! Keiki Worries, Ragged Roots, and Funky Fungus

[Sprue]

Hello, hello!

After expressing such joy in carefully watching over an orchid my mother got for her birthday in March, she surprised me with one from Whole Foods weeks later!

I examined the roots while changing the dense spongy stuff it came in over to Ferti-lome Orchid potting mix (has bark, peat moss, volcanic rock, and charcoal pieces). I noticed its roots were trashed (As I later read can happen with grocery store plants).

Armed with hope, and the internet as my guide, I sterilized my scalpel, hacked out the slimy black bits, doused the poor thing in cinnamon, and crossed my fingers.

Since then, it seemed okay. It put out a new leaf not too long ago. I had it and my first orchid on the back patio in indirect light when temperature and humidity were right, and inside facing an indirectly-lit southern window on plates with gravel and water when temperatures outside aren't right. I water them once a week and fertilize every couple weeks with Carl Pool Orchid Food.

One terrible week in late May, as the brutal Texan summer was gearing up, I had my wisdom teeth surgically removed. The week and a half of pain-pill haze allowed me to forget my pain and my leafy little friends in the heat without water.

Each lost two blooms, and over the next few weeks, lost all their blooms and their spikes began to decay. Both of big orchid's spikes are dead and gone, but little orchid just has bits of decay at the tips, extending farther and farther down over time.

A few weeks ago, the little orchid started working on a keiki! Albeit, on a dying spike... Initially, I was elated I would be a grandmother. But, I soon read that it could mean the plant is dying.

I (perhaps stupidly) cleared away all the potting mix and found yellow-ish/orange-ish spots on only the bark pieces of the mix. Fungus? Mold? This has actually occurred once in the other orchid before, and has returned despite a repot.

Sadly, I discovered the roots seemed to be worse today. There was no new root growth (my other orchid has had a little bit of root growth in the same time frame) and black wet areas in the middle of roots.

So, from my conclusion, the keiki is born from stress, not great care. I'm heartbroken.

I'm wondering if there's hope to save the momma plant? The keiki is so young it won't survive on its own... I'm not expecting it to live based on momma's current status.

TL;DR
Young orchid has started to grow keiki. It has lost all its blooms and both spikes are dying, including the one the keiki is on. Its roots were in okay shape when purchased and have shown no improvement. There is a mold or fungus in bits of the potting mix. What can I do to save both mother and child?