Hi
I am so sorry, but it DOES look like dropsy/bloat....

the pictures are a bit fuzzy but it is a very common occurence in ADFs...I lost quite a few this way over the years...
also, it is contagious, so remove the sick frog from a tank with other ADFs. Most often it is fatal, but if you keep him in his own little tank with EXCEPTIONAL water quality there IS a chance he can recover....
Its about a 25/75 success rate but if you have the space and tank for him to live by him self for a bit I would try it.
Keep shallow water....no more than 1.5 to 2 inches....they can develop swimming problems and you dont want to stress him out or have him drown
very tiny feedings....and hope....
also....(almost forgot!) Maroxy (spelling?) is a medicine that may help cure your frog, and you should give a minor dose to the main tank to help prevent other ADFs from becoming ill.
Maroxy helps cure bloat, dropsy, fungal AND bacterial infections of ADFs and ACFs (miracle solution anyone?)