You describe two completely separate things. Some experiences and perceptions that you think are different from other people's.
Then you have a belief system that has been presented to you as incorporating and explaining those symptoms.
To seek an explanation for the first thing, see your doctor. Take a list of all your symptoms, how long you've had them and how frequently you experience them, so you don't forget in the moment and so that your experience cannot be dismissed as trivial.
For the second; there will be many, many different belief systems that would offer a way of explaining your symptoms, if that's something you want. Just take your pick of religions and you'll find it if you look. All the major religions incorporate some mystical elements that discuss visions, altered perceptions etc and that probably arose as a way of explaining the feelings and behaviours of people who were neurodiverse or experiencing episodes of mental ill-health.
The sect or cult you're dealing with is just one more in a long line of sects or cults that do this sort thing. Somebody's pet project, creating their own mini-religion.
Whether your contact truly believes in this cult's vision, or is just using to prey upon and manipulate people is irrelevant. What matters are his actions and their effect on you.
What does your husband think? You've discussed the creepy bloke with him, haven't you?
Were you asked not to? To keep it 'our little secret' in classic grooming abuser parlance?