I knew you would bring up DahnHak--that's why I almost didn't mention it. This is something that all kinds of businesses send their employees thru, tho--so it seems less "sneaky/secretive" than the DahnHak stuff was. Also it is not a "spiritual" thing--it's tools for living. But--I had some of the same thoughts and fears and they are a bit into getting you to get more people involved. My main thing that says it's okay to me is that the lady who got me to go (and paid for it for me) is a very decent person and I have known her for 2 years. I can see how it helped her and also a bunch of others now that I went--so I have less concerns about it now.
Do what resonates with you and trust yourself. I just wanted you to have options.