Not that I'd want to press for just another change because we need to get going here,
but if the event is ever repeated I think it should be:
-Round 1: n/a (9 Champions to win)
-Round 2: 8 Champions to win.
-Round 3+: 7 Champions to win.
or even
-Round 1: 8 Champions to win.
-Round 2+: 7 Champions to win.
Reason: Budokan is supposed to be medieval Japanese-themed ...
If you have ever seen Japanese Bushi-movies (or know a bit about Japanese martial arts),
sudden death is what adds the flavour to them:
Even experienced warriors die, sometimes in masses, within the blink of an eye.
The dueling-art of Iai is foremost about "drawing the sword" ... a whole rock-paper-scissor system
exists to decide a sword-duel in the very moment the blade is drawn. A matter of seconds.
Budokan is also a dueling event and not a battle simulation.
If a team displays extraordinary "skill" and finishes quickly with all contestants winning their duel,
be it in the first or second round, it should be rewarded accordingly.
After all, it really isn't all that likely to happen.