Run tests too
Including all those people in Indonesia. The last thing you want is for 80 people to flood the bandwith and have noone able to watch.
So no matter what you end up doing, do a "test wedding," one in which you are broadcasting from the location of ceremony, and those watching are watching from the location(s) at which they will be viewing. Might also be worth some investigation to see if your future in-laws to be can host one big viewing party rather than having potentially dozens of different IP addresses trying to stream the same data. This might end up being more fun for them, anyways