Maybe it’s simply because he’s not the sitting president and his detail is much smaller?
USSS details are heavily supplemented by locals for events like this. Even if the USSS team was relatively small, somebody – whether it was USSS, local, or state police – should have had a location that blindingly obvious secured. That building was literally the only real elevated position with clear line of sight in the vicinity of the stage. The fact that somebody could get up there without immediate security response is really almost unfathomable if it weren’t for the fact that it happened.
Or you tell them that you do.
Per hour.
But since they’re clearly such great mates with dad, you can cut them a deal.