Congrats on the hatch and growing youngsters! Sorry about your poor rooster.
Don't know about the mystery chicks being Cochins if they have featherless legs and feet. It's been a few years, but I think my Cochins showed their "fancy" feet and legs pretty early on.
Best wishes with ALL of...
I will always have a soft spot in my heart for Buff Orpingtons; one of my original hens was a BO, and she passed away last year. But not before she made sure everyone knew she was the QUEEN, albeit a kind one.
Best wishes with hatching those eggs -- let us know when you have chicks, please!