So sorry it took me so long to get back to you about this... I hope the frog is still doing ok.
I made a few calls today, the last one being to a vet clinic I am fond of for their expertise in reptiles and amphibians. It was a very in depth and lengthy conversation about your frog.
If its any reassurance to you, I was told that I appear to have the best grip on the situation that they could imagine, as well as the right ideas for treatment... but I really need to explain to you what you and your frog are up against here.
This type of bloating in the dwarf frogs is common, but because of their size, their vulnerability to diseases, and fragility in body structure, this is a very difficult problem to treat. This is not an animal we can do a biopsy on to be sure of what we're dealing with, and there are a great many things that can cause the bloating, bacteria infection is one of those things... but there is also kidney and liver shut down, heart disease or shut down, etc. There has not been a lot of scientific research done because of the fragility of this species of frog... most attempts at lab work are lethal, leaving us only with necropsy to use for true diagnosis... and by then its obviously too late.
To be completely honest with you, your frog doesn't have a lot of chance of surviving this, and should be quarantined, especially if there are other frogs in the tank. IF this is indeed bacterial based (bacteria can cause organ damage and malfunction, also) it would be highly contagious, and my past experiences with these problems (also the vet's experience) shows us that whatever this is, is contagious to other dwarf frogs.
Frogs are more challenging to medicate because of the absorbtion rate through their skin, and the vet agreed that one of the key factors in treating this, if treatment is possible, would be by medicating the food and being very careful not to get the medications into the tank water.
To do this, I would strongly suggest a quarantine tank with a good filter, filter media including either carbon or, if possible, PuraPad
should be used at all times, to help absorb any medication that may get into the water, and frequent small water changes.
The medication the vet and I decided would be the safest and most likely to work would be amoxicillin
treated food. Because your frog is still eating, and accepting live food, this should be relatively easy to get into him. 1 dose of the med into a 1/8 - 1/4 cup of tank water, be sure it dissolves completely... then add the live worms and let sit for 15 minutes so the worms have a chance to absorb and consume the medicated water, then feed the medicated worms to the frog. I would not do this in a tank with other animals, or a main tank where you have less control over cleaning and removing any traces of meds from the water.
Keep his temp warm, 78F - 80F, water as clean as possible, and some kind of shelter for him to hide in.
1 of 2 things will then happen. The frog will either begin to show signs of improvement, in which case I would continue the medicated food for 10 days, or the frog will die, which will happen anyways if we do nothing. The survivability rate for this type of problem is very low, I'm sorry to have to tell you that... even with the meds. The above treatment is his best chance if you can accommodate it.
Best of luck to you and your frog. If there is anything more I can do to help please let me know. Please keep me posted on his condition.