growth on giant gourami

[lstrong]

I have a 3-4" giant goourami that i just purchased a few weeks ago.a few days later he started to get a raw spot on his side.I thought it was an injury from another fish so i put him in his own 10 gal tank to grow him out before he went in my big tank.Now he has several raw sores on his body with the worst one on his face near his mouth.You can actually see into his mouth through the sore.I tried to treat it with salt,melafix and pemafix,and general cure from aquarium pharmaceuticals.no change in sores and they continue to grow.My questions are
1.what is this
2.can it be healed
3.should i euthenise the fish



I know the pics are bad cell phone pics but they are the best that I have.Please give it your best shot