"Trail Life USA expects to become a premier Christian organization....Trail Life is a way of life that is centered on following Christ in the outdoors...Adult leaders of Trail Life USA will be Christians who sign a statement of faith and submit to background checks."
So how would a Jew be able to sign a "statement of faith" that they're a Christian and will commit to "following Christ in the outdoors"? To a Jew, Jesus is just a Jewish carpenter, not God.
If the article instead read "Adult leaders of Trail Life USA will be people of faith who sign a statement of belief in Judeo-Christian values", then a practicing Jew would be able to join.
I see. Well, start your own organization, then.