Are Tiffany Fontenot’s conclusions about the false nature of the channeled Ra material correct because of her reverse speech analysis being accurate?

This was a correct interpretation, and the reason is that the channeler herself had inner conflicts from two directions. On the one hand, she had an intuitive awareness all was not what it seemed and was having some doubts about her reach. In addition, there were some misgivings from receiving impulsed knowledge from the divine realm to pose countering views and alternative choices for consideration, not to override what she was doing and saying but simply to raise questions for her to consider, and this was enough to fuel the inner doubts a bit further. So the consequences did show up in the reverse speech analysis that was conducted, and in this case the conclusion is correct, although the methodology has its pros and cons and is subject to much subjective interpretation and hence has remained quite controversial as a consequence.