Interestingly... in 2015 Klayman filed a defamation lawsuit against Risen for what he claimed about Montgomery. Haven’t heard how that one turned out.
In that case the defendant was granted a summary judgement.
“Second, without record evidence demonstrating that Montgomery’s technology actually worked, Montgomery is unable to show that there is a genuine dispute of material fact regarding the material truth of the Chapter’s assertions, and therefore cannot support the element of falsity.”
https://www.courtlistener.com/opinion/4238906/montgomery-v-risen/