Ben, even when calmly told the truth, some people will get defensive and disregard what they are told, so be prepared for that. We see this happen relatively often here on the forum.
We all get to have healthy boundaries. If we speak the truth, and someone claims we are attacking them, that is their issue.
Reading up about Scientology can be very useful. So many people, in so many ways, speak the truth about Scientology. Yet cultic beliefs are stubborn.
Keep writing, keep noting things down on a list. You can write here, this forum is read quite actively, and there are many knowledgeable folks here. You can tell us what you know, ask questions, and learn from all sorts of discussions here.
This cult education forum can be helpful too
https://forum.culteducation.com Read through this site
https://www.culteducation.com regularly to get ideas on how information about cults can be communicated.
You could run your own blog. Some examples of education blogs: This about a cultic New Age group
http://psychologyofvision.blogspot.com, and this on Scientology
http://tonyortega.org You could post flyers around town with your your blog url. You could run a related Facebook education page.
Here is Cult Consulting Australia
http://www.cultconsulting.org/about-us (I don't know anything about them.)
What is the best process for disseminating that information so that the truth can come to light?
The best way is to keep at it. Keep writing, posting, talking, learning. You may have been taught to walk on eggshells, taught to believe that you have to behave and think a specific perfect pure way. But you don't have to walk on eggshells. You get to try things out, make mistakes and learn from them, adjust and refine as you go along.
The cult I was part of still exists. But there is now a lot of information about them online. They sued a cult expert for daring to call them a cult - and they lost in court. That process generated more public information about them.
Your information may save someone from falling for Michael's deceptions. Your information may help a current follower begin to think more clearly.
If you know of anything illegal, please do report it.