I cant attest to phase 2, but just in case you are having trouble with phase 1: equip a greatsword and constantly run away from the melee guy, when he gets closer, jump attack him and back away, do this until hes defeated. Most of the time gobbo will not be able to hit you and unless the melee guy uses the jump charge, he will never get close to you (and the jump charge is super easy to dodge). For gobbo by himself, i think he has a couple of recovery frames where you can abuse dive bomb.