Hi, welcome to the forum.
I am sorry you and your betta is going through this. I am not an expert in treating diseases, so I will help what I can, there are lots of experts on this forum and I am sure someone will chime in later.
From the look of your photos, which you did a great job taking them, showed that he does have pop-eye which is also cloudy. I am not sure what the cause may be, but my first thought is he has septicemia which went untreated thus becoming this way. Are you able to get your hands on broad spectrum antibioctics? Kanamycin or Maracyn I & II ? For now, put him in a 1 gal quarantine tank with same temperature water and put in 1 teaspoon of Aquarium Salt (NOT epsom salt) with conditioner and stresscoat/stressguard if you have any. It's not a bath, so must leave betta in the solution after it's dissolved and mixed well. In the meantime, you need to go get antibiotics as soon as possible.
However, please also fill out this sticky as we can try to understand the exact cause of this wound and also the prevention of it in the future.
Good luck!
Oops....posting the same time Sakura did.