That's the plan. They have targeting Burr as the best chance for taking over the Senate without the consent of the voter. The Governor of NC is a Democrat and would appoint a Democrat if Burr resigned. They probably have another chump lined up as well.
As for the charges, it's unlikely that they have a case. The signs of big trouble in the travel industry was in the public domain before Burr sold his shares. I don't think the the insider trading accusations will work for any of the Senators who have been accused.
Feinswine was the only one who had sales that could draw questions, yet the left will gladly throw away someone with a foot in the grave in a SAFE DUmocrat district if they can take down 4 or 5 republicans giving them just enough to prevent 60-votes.