Assuming he really does believe the stats against their anti-gay marriage position, this could be a desperate attempt to rally the troops to redouble their efforts. Remember, primary tools of the Right are fear and a common enemy. The enemy must always be at the gates, or people will lose interest and go back to their ordinary personal interests.
I could interpret this as a classic "the enemy is at our gates!" battle call. Plus by singling out the young people, he could be alerting right-wing voters and politicians to continue passing laws that even outlaw the mentioning of gays in schools, as just happened in Tennessee. And the removal of GLBT school programs, anti-discrimination laws, etc, etc.
If they won't listen to our message, then we'll force them to comply with us. And punish them if they don't. Again, pure right-wing tactics.