I like your take.
Kash says that in a federal conspiracy case [(RICO)] that when any single conspirator moves even for a second, into another state, that the Justice Department (Durham) can then file the whole conspiracy case, right there.
So, picture Durham has all the principals threaded together that he wants, and say Sussman orders a coffee from a drive up window in name-any-state, Durham can go full Mohammed Ali, on the whole ring, against all conspirators, right then and file RICO, or, whatever they’ve now changed the name of the charge to, there in that state.
Nowhere near DC.