I had a somewhat similar VIP "encounter" on a PS flight 2-3 years ago (can't recall the exact date, but I do recall it was the old PS bird since I was in 9A, with the huge legroom, and VIP was in 9C (aisle seat on right side). The entourage pre-boarded before any other pax, and the big guys stood by him, until closed door call when oddly they sat in the rear. I really thought with all the security one bodyguard would be seated with him in C (I was also surprised he wasn't in F)

When we arrived LAX, there were 2 or 3 Escalades parked next to the Jetway, and the entourage all walked down the stairs and hopped in.

I never did figure out who he was.

I'm a little surprised they would hold a flight for a high security VIP. What I observed makes more sense that they would want to have security in place before anyone boarded the flight.