Infection + Axolotl Not Eating | help appreciated

[Dalton'n'Darwin]

TL,DR:
-I've been hospitalizing her in a mini-fridge at 7-10 degrees Celsius (45-50 F.) and giving salt baths/changing water while I sanitize and cycle her tank. (currently nearly ready to begin cycling) (later note: now cycling)
-This morning, the skin on her sides was covered in white growths. (later note: this may be her skin reacting to salt solution ? )
-She is not eating, appears to be thinning out,
-She may have been sick and injured from the infection. (later note, pictures attached)

AS OF July 13 -
My wildtype Axolotl showed fungus/collumnaris on her gills one week ago.
It's been tough to keep the fungus at bay with two 15 minute salt baths each day, but I know she's been sleeping well in the fridge between baths. She pooped about 5 days ago, and last ate about 8 days ago.
Now, she isn't interested in food and is beginning to look thinner than before.
She has been gulping air more and more often, currently about every 10 mins when she's awake.
Her gills have taken some damage from the infection, but not a lot. The fungus has spread over the last week throughout her gills, but is no longer eating down to the stalks, which is an improvement.
Here's where it gets messy; Last night, I messed up. I wanted to do a third salt bath that evening to try to get ahead of the infection and when I put her back into the fridge, I'm pretty sure the water did not stay cold enough overnight. She's been asleep for a while, and was likely awake/moving around in her confined space and probably stressed out. This morning, she had similar white growths spread pretty extensively down the sides of her body. I gave her a salt bath and most of the growths came off with some gentle brushing, but they were obviously damaging her skin. Behind her front legs and dorsally from her back legs (near her pelvis), the infection has left what look like dark brown sores in the skin. They look painful, but she seems pretty stalwart about it. I've offered her food every day, and she hasn't taken anything. I used a pipette to try feeding her her regular bloodworms directly today, and she maybe took in some of the food, but is still not 'eating' normally like she was before hospitalization.

She's tough and pretty smart, but I'm suddenly unsure of how to deal with a situation this severe.
I'm not sure what exactly the infection is, but I have magnified photos of infection samples from my home microscope, not sure it's powerful enough.
I'm going to get a small air pump for her and will continue salt baths.

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--> UPDATE: I've kept her cold and in a Methyl Blue solution (almost half-strength), and the growth is starting to return all over her sides and gills less than 8 hours later. I have implemented a low-pressure air pump for water oxygenation, and I'm going to keep doing salt baths, but should I consider wiping all of it off with Hydrogen Peroxide just to completely eliminate it?
(based on the spread of the infection, I think this may be fungus (saprolegnia), but I'm not sure I should really rule out columnaris. Will Hydrogen Peroxide kill fungus? What should I do to treat it directly if it is?)

 

[Dalton'n'Darwin]

Note: trying a Black Tea Bath tonight, tank cycling begins without issue, photos of her current state attached. (just moved into the tea bath with frozen water bottle added for cold)

In the 'close-up' photo to the right, I have captured what can be seen of the 'sore' above her leg.
Note: white growth continues down her tail between the upper and lower muscle groups.

I'm making sure as I can that she gets enough rest and remains as calm as possible.

Any and All help appreciated, Thank You.

 

[Dalton'n'Darwin]

The white growth along her sides has changed to a grittier texture since this morning.
I'm hoping that this only means she's been exposed to too much saltwater, so I'm probably going to switch her to Tea Baths instead and plenty of rest in the dark cold fridge. Now that she can sit next to an air stone, she is gulping much less air and seems more calm. Before she seemed weak and tired, and now she is a little more active, but still somewhat sluggish.
I'm not sure, but her gills might be filling out a little once more, but there is still some growth throughout. The growth on the gills has been tinged green/blue (I suppose from the Methyl Blue)
I will try to be as delicate with her skin as possible tomorrow as I swap her to/from baths.
(Still need her to eat food soon, and I still don't know for sure what the infection is yet)

 

[JM29]

Will Hydrogen Peroxide kill fungus? What should I do to treat it directly if it is?

Yes, hydrogen Peroxyde will kill fungus, at least already developed fungus.
But you won't eradicate it since fungi regularly come with microscopic spores in air and water.
Moreover, I don't understand very well where you want to reach the fungus to kill it. Hydrogen Peroxyde may be harmful for your axolotl.

You're hospitalizing your animal. Ok, but if you talk about a systemic infection, it means there is something bad in your tank (too much decaying organic matter ? too hot ? ...) and you'll have the problem again.

 

[Dalton'n'Darwin]

it means there is something bad in your tank

I've cleaned out my 20 gal, bleached for the infection, and am now beginning to cycle it again. I figured out how and why it happened, and shouldn't have any problem reintroducing her once she's clear of infection.
Thank you for your reply. I'm not sure I want to use hydrogen peroxide as long as her skin clears up, but I'm glad to know that Hydrogen peroxide will kill fungus, too.
I found this great resource on Collumnaris bacteria, so I have that. (Notes on Columnaris) If her skin is just reacting to the salt solution though, I still am not sure what kind of infection it is.

 

[Dalton'n'Darwin]

I gave her a day in the cold dark fridge with water changes to recover her coat if that was the issue, and the infection has grown far worse. I'm sure I've taken the wrong approach here. She's highly stressed and very unhealthy.
Taking this as a learning opportunity, I find that this is almost certainly a Fungus infection. Salt baths are much better than Tea Baths. It's difficult for me, but Keeping the temperature changes as mimimal as possible will help with stress. Partly submerging the air stone decreases both it's pressure and movement, which means less stress as well.
I'm still not sure if she will eat.
Other things that I'm doing are using a remote grill thermometer to tell the temp of her water at all times (works suprisingly well) and putting her mostly-covered container (plus whatever water will fit) in a minifridge with the light off so it does not turn on when I open it.