No constitutional scholar would be split. If they suggest otherwise they are lying. This is one of the few things spelled out so clearly in the constitution as to leave no doubt. The only doubt wouldn't be from the constitution it would be from the technical definition of insurrection or rebellion. Basically if they could argue successfully that it was neither then amendment 14 section 3 doesn't apply but if it was defined AW an insurrection or rebellion then it isn't really up for interpretation. Even SCOTUS wouldn't be able to overturn that without destroying their legitimacy and causing a constitutional crisis.

I could see the more extreme justices arguing that it doesn't meet the legal definition of insurrection or rebellion but I think even they must know that this has to end and that making that ruling would have consequences they wouldn't want.