The rocket and meteor

What exactly are Cloud and co doing trying to stop Shinra from destroying the meteor?

I guess I get that they want to preserve the huge materia, but like, that doesn’t do much good if the planet is destroyed.

And after fully sabotaging the mission, the rocket flies into it and fails to stop it and everyone’s like "damn, was hoping that would work but Shinra failed."

Didn’t it fail BECAUSE we basically looted all of the explosives they were using to destroy it?