The Seanchan believe that the Aes Sedai are murderous monsters one and all. That if you goto sleep at night, there is a possibility of a Aes Sedai killing you in your sleep. The Aes Sedai are their bogymen, plain and simple. And the Sul'Dam did have a choice as Tuon made ever so clear - they could simply decide not learn to channel and disappear into the country and live quiet lives.

Tuon was insistent on what the Seanchan believe channelers to be, thieves and murderers and the worst scum the universe has ever created - to be imprisoned and controlled before they break the world anew. Given this cultural baggage, and other options instead the Sul'dam embraced channeling. They badgered the Aes Sedai, Evil Incarnate in the eyes of their culture, to train them.

Julian Sandar, a Tearian who was raised with a similar set of beliefs and same type of culture as the Seanchan and Children, with a few weeks of association with a channeler, realized that what he was taught was fundamentally wrong. That only took a matter of weeks.

On top of that there are the people who follow the Dragon Reborn. After three thousand years of hearing about what the Dragon did, and all the male Aes Sedai, people are willing to drop their preconceptions to follow this man. Men are willing to channel, and women who should be absolutely terrified of those prospects instead come and join their husbands as they learn to channel. They accept this new twist of events.

I submit that the hardest core and most twisted faction of the Children, those who will never change, stayed behind with the questioners when the rest of the children broke away with Galad. Thus, those remaining are far more likely to, if not lose, at least mitigate some of their hatred for channelers.