Sending foreign troops of any sort in to "pacify" the US population simply isn't going to happen. No way, nohow, forget it. It would set off a civil war, or at the very least increase the casualties as "cultural differences" of various sorts caused chaos.
Now, did a British ship in the area let of a few Ghurkas on shore leave in Hawaii? That I'd believe. Even some sort of joint special-forces-type training wouldn't be inconcievable, the US and all the other NATO countries do that fairly often, it's no big deal. Since the Ghurkas are considered "elite troops", there's no reason they wouldn't get involved in that.
Jim