Very Sick 6 y/o Rooster

[Vgcmd1962]

Help me please. He was fine until 8 days ago when he suddenly just wanted to lay down and exhibited weak legs. The following day developed crop stasis. Took him to an Avian vet and X-rays revealed illuminating foreign objects and he gave me IM and oral chelation therapy. Despite 2 days of IM chelation he worsened. Got weaker and developed dark yellow urates. Took him back and vet decided to surgically remove the foreign objects. Never obtained zinc or lead levels. He stayed 4 nights at his clinic. Vet believes the yellow stools are signs of liver failure and gave me lactulose and an anemia supplement because he’s very anemic. Well he’s home and is very sick. Can barely stand and walk. Takes a few steps then falls. When he sits opens his wings and has open beak breathing. Vet did not recommend to resume chelation therapy. Last night I decided to resume. It is oral. Can this be liver failure? He never got any blood tests. Can this be Marek’s? Any ideas what this could be?