The planet could barely handle the power of the obsolute Monsterous power of both Brolys, each hit from Broly (new) is shattering tips of mountains but Broly (old) isn't even FAZED by this somehow.
Vegeta (mind)-"Just what the hell is this guy? He knocked Kakarot out so easily... That won't Reassure me. I need to fuse but why shall I do that embarrassing dance? Why should I merge with a low class?"
Goku- "VEGETA WATCH OUT HE'S A BROLY FROM A DIFFERENT DIMENSION YOU CAN TELL FROM THE PUPILS OF HIM AND THE PRESENT BROLY IN LEGENDARY SUPER SAYAIN FORM! WE HAVE TO FUSE HES GOING TO BE WAY TO MUCH IF THE CURRENT BROLY AWAKENS LEGENDARY SUPER SAYAIN WITH OUR TRAINING HES GOING TO BE A MONSTER SO ITS BETTER WE FUSE TO TRY TAKE HIM OUT NOW!"
Vegeta- "WAIT WHAT?! THATS IMPOSSIBLE!"
The sayains were in grave danger since the training with the new broly will make his legendary super sayain a godly threat. What they had yet to realize was that the new broly learns and old broly was already growing more in power doing nothing but breathing. This is way too much for even Vegito and Beerus if it stays for way to long.
???- "Hello again mortals."