They should bring the husband in for questioning, along with the guy Kate met, and Kate.
It’s a very very convoluted mess. At least 100 theories about who was going to do what at the rally.
Target could have been POTUS but more likely a member of the media.
Any attempt from anyone in a Q shirt or even if they knew someone that had once mentioned Q would be enough for the media to be on a 24/7 mission to take down Q.
There was a threat at some point prior to the rally but it is still unclear who/what the threat was.