Funny, here in The Netherlands, my son recently joined as I also had fond memories growing up with the scouts. I don't remember anything really religious except building the make-shift christmas church with the animals and a renegade priest in the woods.
I was actually disappointed that God was left out of the vow (I am catholic) with my son, perhaps I should have asked. I don't know where you live, but do you really think the in your opinion bad things, the frequency of socalled forced prograganda, outweigh the beneficial things like playing outdoors and hiking in nature?
Regarding religous education, you can't choose if you don't know what 'religion' entails. You can't explain it to your child as you have an anti-religious stance (which I fully respect), so he will have to find out for himself anyhow later on if 'choice' if something you value (or not). FWIW, I consider religion a metanarrative and vocabulary for the existential dimension of life, like playing mystical Nordic LARP stories. The sooner a human learns to speak or aprreciate it (in whatever form) the better imho. A vow to the Akela and the troop, fine... it's a vow to community values not to some sort of demi-god or god.
https://twitter.com/fsiefken/status/741687278796431360