Here's a link showing different ways a sex-link rooster can be marked. These all have single combs but there are some that have the comb your bird has. I just can't find it through google as of yet...
http://laughterherd.blogspot.com/2008/03/sir-buffington-buff-rooster.html
poultrykeeper, they can and do use Wyandotte Hens with a RIR rooster for red-sex link crosses.
He looks nothing like these birds on this page:
http://www.feathersite.com/Poultry/CGA/Cornish/BRKCornish.html