comb rot?

[Roxychick]

My rooster has recently developed a crusty dark comb and it looks to be eating into his comb. He’s eating like normal nothing seems to be an issue except for his comb. What could this be and what should i do about it? If it’s fungal would applying benzoic and salicylic acid lotion help?

 

[Wyorp Rock]

Well, this is different.
I don't believe I've seen this before even in photos. Is the same thing happening along tissue at his beak too?
Any way you can get a few more photos - other side of comb, from the top, his cheek, etc.
The tissue around his eye is swollen too correct?

What does it feel like?

I'll tag in @Eggcessive @coach723 to see if they have ideas.

IF you were to take a wetted paper towel and gently swipe it (don't rub) - is there anything that comes off?
I would also look inside his ear - any debris in there?

 

[Eggcessive]

I haven’t seen anything like that before. Do you have other roosters who could have pecked him or run him into fencing? The benzoic acid may help treat a fungus. Other possible things to use against a fungal infection would be clotrimazole, miconazole (anti yeast cream,) ketoconazole, pine tar, or povidone iodine.

 

[coach723]

I've also not seen anything like it before. My first reaction was wound and dried blood and/or scab, but not sure that is correct. I think I might go with the iodine since there is a question about whether it's fungal or not. If it's injury or bacteria then the iodine would also help with that.