That looks simple to me. Maybe because I’m totally ignorant?
KEY EXCEPTIONS TO THE POSSE COMITATUS ACT
“Pursuant to the presidential power to quell domestic violence, federal troops are expressly exempt from the prohibitions of Posse Comitatus Act, and this exemption applies equally to active-duty military and federalized National Guard troops.”
IOW, implementing Martial Law or the Insurrection Act. Yes, AD and federalized NG are Title 10 forces @ that time. In the current situation, Posse Comitatus is the rule. NG is under state control (Title 32) right now. If and when one of those two situations would arise, the application/relevance of PC would be the least of the issues.