Ok got it! Pics were self explanatory. He is very stressed out and being in KK is not helping, put him back, add way more plants, branch or two, so it'd look like forest of sorts. Cover sides of the tank with anything not see through and leave him alone for a few days, then offer crickets. Dont use glass bowl, some frogs are not getting it right away, so just drop crickets in a tank.

Fecal test wont hurt to do anyway, if one frog has parasites, both will need to be treated.