They're both not crowing anymore??

[KikiDeAnime]

Do you mean egg membrane? If so, have you been feeding them eggs? Otherwise how else would egg material get on cockerel's necks?
What you are saying is not making much sense so far. Hopefully someone else will better understand what is going on.
How old are they?

Both roosters are around 4-5 months old, possibly already 5 months

 

[KikiDeAnime]

Update:
We lost Chocolate during the night. Silver was pretty upset about it and actually attacked me when I tried to remove him. Something fell off of the dryer during the night and hit Chocolate, pressing him against the wall of the tub. I'm sure it was my fault for not putting their tub up higher to prevent this