They didn't involve Law, Kid or any of the Worst Generation.
That much we know for certain, as the Supernova were late additions on the feedback of Oda's editor at the time, Onishi (former Gintama editor).
The Worst Generation were never intended to be as consequential as they were. Oda planned to kill off most of them to show how tough the New World was, but changed his mind over time.