Jan, at least, appears to be allergic to the word "faith". His argument for God is that he just knows that God Is. Not so much faith, but direct, divine inspiration. Jan has a special gift in this regard.What Bowser, Jan and Musika are not saying is that the reason they believe the answers point toward God - and not to some other entity - is because they have faith.
I don't recall Bowser or Musika using the word "faith" to refer to their own beliefs.
In fact, it would be good to clarify whether they infer God by looking at the "evidence" (like Bowser's pile of bricks), or whether it's more a case of choosing to believe. Or maybe they have direct contact, like Jan says he has.