Hercules Mulligan may have took the measurements and information but he sure as hell didn't smuggle it
But you know who did? His slave, Cato.
Cato was a courier and spy, helping gather and pass on vital intelligence to Hamilton, their contact at Washington’s camp. He’d be sent to a shop with tailoring ads to translate into German for the Hessian soldiers where he’d meet with a fellow spy Heym Salomon. He would then return back with translations and information which would be hidden in packages containing clothing.
As Mulligan’s tailor shop catered to high end British officers, many soldiers had seen Cato running errands for him before and didn’t expect a black man to be the one passing intelligence on George Washington. This meant he could cross the Hudson River without seeming too suspicious.
He was even jailed and interrogated after some suspicions did arise about Hercules Mulligan’s activities and the deliveries but didn’t talk. He also was the one who delivered the messages which helped foil a plan to kill George Washington.
Tl;dr – Cato didn’t even get a single mention in Hamilton and because he was a slave he’s been almost brushed out of history. Just know that he was every bit as important as Hercules Mulligan and deserves to be known.