I'm afraid it's your argument that lacks merit; requiring a "duty to god" is a religious requirement, and public schools can't enforce this.
And yes, the BSA practices religious discrimination. They kicked out the Randall twins in California. They kicked Rick Sherman out of an Explorers post run by the municipal police department (back when the BSA expected government-run Explorer posts to discriminate; they don't now, but it wasn't the BSA's idea).
Like I've said, you can continue to ignore the problem by pretending it doesn't exist, but 1) according to the BSA itself, over 10,000