Tom, Whether or not the cult had enough to get their initial order against John even without your affidavit, they certainly didn't think so and I don't think you can justify or excuse your actions on that basis. It's not as if you were handing a bad guy a gun you knew all along was inoperable. In fact, the cult DID use your affidavit so whether they could have gone after John without it is a very small and moot point, in my opinion.
I think the real problem here for you, ethically speaking, is that, notwithstanding the fact that John betrayed your trust and left a trail for EV leading to you, you made a very cowardly and unconscionable decision just because you couldn't be honest with your wife. I know you hold her in the highest regard and all that but, frankly, the very fact that you felt compelled to stoop so low ultimately reflects poorly on her as it does on you. After all, what kind of person needs to be protected from he truth that way? One can't help but wonder what might have happened if you'd had the guts to be honest with her? If admitting that you'd leaked the docs to John was enough to threaten your marriage, that's a sad commentary on yor wife's priorities. You suspect that Maharaji comes first. So long as you don't threaten her relationship with her cult leader, you're welcome to stick around. Nice.