With the absence of the 4 ancient Princes, of any of those 3 Princes discovered that planet and chose to cause havoc and disrupt their plans there, none of their commanders will single handedly be able to stop them.
Collectively, yes…
But if they cause too much chaos in that world when the heavenly bond isn't weakened, it would have alerted the heavens.
In the end, the war was actually there to keep these 3 princes busy and always on their toes and out of whatever plans they had for that human world.
Of course, these Princes didn't dare to venture into their territory all this time that they were away, because they thought they were still in the abyss.
Beelzebub slowly made his way to his throne, missing the comfort it brought him.
Looking at the underlings on one bent knee before him, Beelzebub slowly eased into his throne seat.