NAL but here’s my own small dive into the “what does insurrection mean” argument …
The 12th Amendment clearly states how the President is chosen, and Section 3 of the 14th Amendment states that no one may hold office if they “engaged in insurrection or rebellion against” the Constitution.
It’s the “or” between insurrection and rebellion that’s important here as it means the definition of insurrection is not vital to charges being laid … the word “rebellion” is easier to define and Jan. 6 was exactly that – a rebellion against the completion of the 12th Amendment where the legally chosen President would be sworn into office.