I'd hate to get rid of that bird just yet. Is it crowing? At 19 weeks, it could definitely have a comb and wattles that red and still be a pullet. I'd like a closer look at the saddle feathers. Are they long and pointed, or rounder/shorter? Long and pointed=rooster. Round and shorter=pullet. In the pic you have posted, I don't see any evidence of long, pointy saddle feathers. There's still hope. I don't give up on a bird until it either crows or lays an egg.