Rot In Cockerel's Mouth?!!!!! Help!

[The Chickens' Maid]

We have a silkie/orpington cockerel who just had his first fight with his two brothers. They are all fine and are healing, but this particular bird has what looks like dead skin(?) inside his beak. I couldn't get a clear look at it because he doesn't like me opening his beak. Does anyone have an idea as to what this could be? If it is anything serious, can the other two cockerels get it?
He is separated with one of his brothers now(no hens, so they are getting along fine). I gave him and his brother a broad spectrum antibiotic. I used the treatment dose because I had already given the flock the management dose. This is only the second time the cockerels have had this antibiotic.
Does anyone have any ideas and advice?
Thanks!

 

[faykokoWV]

any possibility you're seeing his tongue? maybe its swollen.
I honestly have no idea. I feel like I say this in a lot of posts, but hopefully someone will notice and reply

 

[nnbreeder]

Do wild birds have access to their pens? If it looks like a yellowish or white sore it could be canker which can be treated with meds from any pigeon supply.

Another possibility is that it is torn skin from the fight.

 

[The Chickens' Maid]

It looks to have cleared up a little bit this morning. I gave him that antibiotic, and it seems to have helped.
As to what it looks like, it does not look like a sore of any kind, more like torn skin. It's not his tongue; he usually lifts his tongue when I try to look in his mouth. His tongue looks normal
However, wild birds (sparrows and barn swallows) do have access to their pen. He is the only chicken that I have noticed to have this in his beak, the other boys are all fine.