You'll have to focus on preventing infection 1st...
Table salt, cooking salt, or iodized salt, is ok to use, but not "low" or "low-sodium" salt. Please don't leave the Axolotl in the salty water any more than 15 minutes each time, otherwise the salt will start to damage the Axolotl's skin and particularly its gills.
Do you have Mercurochrome? If you have mix it as stated above...put her in it & put in the fridge.
Repeat salt treatment 2x a day & Mercurochrome treatment 3x.
It's important to keep her as cool as possible & stress free.
Is she eating ok?
Deep bow - back, means her back looks like it is bent deep. Maybe because of injury? Is that another wound to the left of the open 1?
I've nursed more serious injuries before, & they have recovered.
Keep us posted, & let us know how things are going, ok.
Regards, Ros.