And invoking the Insurrection Act allows him to do that how?
Moreover, it's POTUS's judgment if, in his opinion, "the constituted authorities of that State are unable, fail, or refuse to protect that right, privilege, or immunity, or to give that protection; or (2)opposes or obstructs the execution of the laws of the United States or impedes the course of justice under those laws.
But it is emphatically not his call to determine whether conditions make it impracticable to enforce the laws through normal judicial proceedings. And that is a requirement for imposing the Insurrection Act in the first place.
See above. If they have CJ Roberts on tape telling Breyer that he would make sure Trump didn't get reelected, there is ample evidence to send him to Gitmo.
It's illegal to detain a U.S. citizen in Gitmo without trial, as any court allowed to operate would quickly point out. So your plan would require martial law and suspension of the courts, Congress, and the Constitution.
Refusing to schedule cases related to the election at SCOTUS, where he is in the minority, certainly is obstructing the execution of the laws of the United States and impeding the course of justice under those laws.
Just because you don't like the verdict doesn't mean courts aren't operating as they should. It just means you disagree with them.