There is waaaay too much emphasis being placed on religion in this debate. Hitler's purpose was to unite the germanic speaking peoples and make them strong enough to resist international jewry.

There was a pagan element to the NSDAP, there was a reform christian element (which afaik hitler supported) and there was a traditionalist christian element.

Hitler did not seem to see it as an important question beyond gaining the necessary support to do what he wanted to do. Time and time again we see him shutting down furious debates (like the one between humainist vs. fraktur), making a decision, and making it clear no further dissent would be tolerated. He seemed to approach religion the same way.

If his movement had been fundamentally christian (as opposed to fundamentally german) it would have looked very different and certainly would not have tolerated any pagan or atheist elements within the movement.