I understand completely your concern, as I felt exactly the same way the first time ours had them! However, never had a problem!
I noticed you mentioned William has had problems with his anal glands. Well, Cleo used to have her anal glands emptied by the vet or groomer, but not after I started raw feeding. It seems the bone firmed everything up, and this obviously helped to express the anal glands naturally!
So, if William's problem is similar you may find the chicken wings could benefit! I really hope so