"Anyway, making assumptions and speculating is all we can do at this point.
There has been absolutely no evidence that a crime has been committed and still it is being assumed that Robert is lying about just about everything and is somehow involved in her disappearance, without any facts to base those assumptions on."
As to the bolded portion above, I think some people are basing their belief upon RT's own words. He said that he failed the polygraph, which showed deception. And he claimed that LE was treating him as a suspect.
So the assumption that he might be lying is based upon his own words, not just raw speculation. JMO