That's great news. I know it's a hard decision. It's so easy to get attached to them especially your first. Unfortunately excess roosters are part of the chicken world. Sorry you have to go through this.
Can you contact the breeder and see about returning/exchanging the roosters? Most breeders will want to make it right. Especially if they were sold as pullets. Sorry about the news.
I've only had chickens just shy of a year. I started off with bantams. Unfortunately, I believe you are right. The pullets combs and wattles didnt develop until later on mine. The 3 Pekin that i have are still very small in the comb and wattles. Hopefully someone else can give a second opinion...