Lymph is a virus. Fungus treatment won't do anything to address it if it is lymph.
I have a similar situation in one of my tanks that is "infected" by lymph. The virus appears to be water born, as other fish in the tank now have shown symptoms on and off besides the suspected original fish. In my experience, the presence of the tumors (or whatever they are) appear to be tied to stress in the tank. It is a 180 gallon community tank of sorts, including a pair of w/c labiatus that spawn pretty regularly. When the labiatus spawn and are defending their brood, several of the other fish in the tank get the lymph tumors. Once the fry are eaten and the tank calms down, the tumors recede. The infected fish seem to act normally otherwise.
In any case, I'm not sure that cutting off the infected areas will "cure" anything, as it appears to be transferred in the water column.
Good luck with your fish. Sorry about the whole situation.