First time I played through SP story mode, I did so mod-less. Using a Barracuda with no torps or mines, I had no trouble whatsoever with the weapons platforms.
But on the second playthrough, this time with Discovery 4.83, even though I spammed torps, missiles, and the most powerful mines I could buy I still couldn't even destroy ONE platform before getting Ye Olde Fission Mailed message. "You failed to destroy the weapons platforms."
Did 4.84 fix this? Does the mod make weapons platforms tougher? Or did it somehow mess with that mission in particular? No problems with any of the missions before that one, oddly enough.