Okay so I have an idea for this challenge that should give us a strategic advantage.
The main time sink of this challenge seems to be from figuring out what to post, and deciphering posts by the other tribe. As such this challenge is easiest if we break it up into a couple roles.
As such I suggest we have 2 Posters, 2 Decipherers/Scouts, and one Cherry Picker.
The Posters will post numbers, but should have some sort of predetermined behavior/lists of numbers already made (such as one only posting multiples of 3). The Cherry Picker will quote all of the posts from our side that are multiples of 3, which they should be able to do way faster than the other tribe.
The Decipherers/Scouts will have the hard job of figuring out which of the opponents posts to quote, and should be very careful to note any patterns in their posting habits, since if we're doing it, they might be as well.