They spent years setting them up. They activated them and ordered them. The FBI recorded this themselves. It got into evidence. Ordered them to attack Whitmer's house. Ordered them to kidnap her. Ordered them to cut her head off.

And I think the issue, generally speaking, is that the FBI rushed this case. They jumped too early for the arrest, as the plotting that was going on wasn't solid enough for them to likely get charges to stick. As it stands now, it's too easy for the defense attorneys to portray what was going on as just some dudes talking shit.