The first part is what I already said.
The second is false. Fraternal insurance isn't about being employed, it's about being a member of a certain group. There are already fraternal insurance programs based on belief, for example Lutherans and Roman Catholic nuns, for two.
And to require any organization with religious beliefs to hire someone who doesn't share those is in itself a violation of the free exercise of conscience.
Insurance is a contract between the payer and the payee. It has nothing to do with a minimum wage.
And ALL believers are responsible for the doctrines of the faith; that's why many groups have catechisms. Your exemption will have to include Sunday School teachers, elders, deacons, council members, deaconesses, worship leaders, prayer leaders, study leaders, fathers and mothers.... all of these are responsible for correct doctrine in many churches.
But fraternal insurance would solve the problem simply: believers can buy in, non-believers can't. It's freedom of religion.
Though I'll point out that fraternal insurance extends far beyond religion. The Benevolent and Protective Order of Elks, the NRA, the American Automobile Association and others have insurance programs open only to members.