Murph means it won't be any tribe that currently in the top 20. I don't think it'll be a tribe that's formed yet, it'll be a merge of loads of good players from all around the world. In regards to Jelly? There's plenty of strong players there, but they're all startup players who'll quit before they hit a million. Not saying they aren't skilled, they just don't, in general, have the history of playing endgame
I think that some of the top 20 will actually be involved in the late game. It is still a guessing game and my opinions on Jelly? certainly are not stable, they are wobbly i.e. not sure if they will stay together or not.