I disagree. Having this person criminally charged for violating a civil contract (the non-disclosure contract with his now-former employer) is a bad idea. The FBI, or even the City of Redmond Police Department, will require that there be at least the probability of a crime having been committed before they'll go in front of a judge.
Whether or not we agree with the law is a separate matter from whether or not a crime was committed -- which they had reasonable suspicion to believe it was. Therefore, they should have gone in front of a judge for a warrant.