You have to assume everyone "gets involved"
Yeah most likely but people have didn’t interpretations and I’m just laying it out as there could be a case that deities pretty much as a rule don’t get actively involved in affairs.
Also Gods draw their power from their place in the creation and destruction of a certain universe, therefore their powers only extend to those in the universe. Luckily in this case that power is over the strongest opponent in Superman.
Then it’s a question of timing, does Dream of the endless vanquish superman immediately or does it take time, maybe requires a sleep? If the former you win as the remaining members of your team deal with the opposition no problem with Wolverine and the Millennium Falcon being the main players. If it takes a sleep then Superman destroys your team and then sleeps, dies and the rest of his team are stood looking at the endless, which is a draw but probably a win on points to the five members remaining vs one member.