Dear Ready,
1) If the cult in question contains no idols than that prohibition cannot apply at all.
2) One can study a cult to see if it contains idol worship.
3) Even with idols, there are exceptions to this prohibition.
4) How would anyone know that a cult contains idols, if they could not study it?
5) I still do not see any reason why you insist cults are forbidden.
6) How do true beliefs exclude cults?
7) How do we know that a cults beliefs are not true?
8) How does the true belief reach us more that it reaches a cult.
“Judaism is the one true belief.”
How do you know that. And how can it be explained as such.