Anybody have a gandar severly injure another or kill another , without blood?

I am watching one of my two Super African 1 yr old gandars who I found unable to walk . He was in his nightpen with sibling and goose, while his mate was next door with a new baby. Everyone had been together , and I had broken up one or two 'tussels' where the other gandar was flailing him on his neck/back and was preparing to move him. But they got along fine until that point. (new baby may have sparked it). I have had other gandars go after a younger one during 'setting season' with another breed, but there was feather ripping, blood etc. (and I know who the aggressive male is in that group)...
There is no blood, no swelling I can find. It has been 3-4 days now... He is eating and drinking.... but moves, by shoving himself sideways with his legs and wings....He partially rose up to try to walk once or twice... I am hoping it is just some kind of severe brusing or inflamation that may go away with time..... If not , I may have to cull him.... He was one of my show geese....dang..... I just would have expected there to be feathers everywhere and blood.... He was fine the day before... and the pen is fenced and hotwired, and nothing has ever breached it.... or gotten any bird....he also does not seem ill, just unable to walk....

 

update. He seems to slowly be improving, can now walk if 'afraid'.(of me)... I did open fence to let the other birds have access and so baby could go start eating grass with mom, and other pair who seemed interested. Unfortunately, other gandar went for him (the adult) , even though he was lying down, and I had to put him alone again... (but next to others pen at night.) Probably the baby set off the other gandar, as he is usually the one who had gotten attacked .... Guess it will be the usual ;keep them apart till babies are a bit bigger and make sure there is a big enough or separate night pen for the family groups. Poor baby doesn't know who his daddy is. He just hangs with the 3 adults, and other gandar is now protective of him AI guess. I am relieved, as I thought it could be a serious spinal damage issue.