Help! Cant tell if this is mouth rot

[Rosearyy]

Please help me! My female betta has recently gotten very sick out of nowhere. Its only been a few days qnd ive been adding ParaGuard as well as epsom salts to her tank but she only seeme to be getting worse. Shes gotten a small white oatch inbetween her eyes. Sorry for the pictures, shes in an epsom salt dip

 

[Rbishop]

Can you give us more information on the tank it is kept in? Full parameters from a good liquid test kit also.

 

[Rosearyy]

Shes in a 10 gal split with a divider (they cant see eachother nor are they ever stressed) it has full filtration and i clean it regularly. Currently she is in a 1 gal for isolation though. She still doesnt seem stressed

 

[Rosearyy]

UPDATE.
This morning she passed away. Im guessing fairly recent since she hasnt discoloured. I tried my best and fought for her as hard as i could but it still wasnt enough.

Id still like to know what took her life if anyone has the knowledge

 

[tanker]

How long did you have her? She may have been sick before.
PS--It does not look like she had mouth fungus.

 

[Rosearyy]

I had her for about 6 months give or take. I saved her from other aggresive females as she was in a community tank, i fixed her up and she had been perfect with no problems until one day where out if nowhere she had gotten sick

 

[tanker]

We never got the water parameters.