EDITED
After watching the movie and reading its specs, Destroyah has the recipe for a Kaiju Killer.
Destroyah is about to invade your city. Its fully evolved. You can pick one Kaiju to defend it.
1. Monsters only up to the Heisei Era (Toho Only). Destroyah was the final one of that era. Can any of its predecessors beat it?
If there are not monsters that can do it, then let's move to scenario #2
2. Any Kaiju (even outside of Toho) but excluding the Anime: I can think of a few. Legendary Ghidorah and Kaizor Ghidorah come to mind. I thought the comics presented a creative way to kill it. MechaGodzilla's Absolute Zero Weapon being used by Jet Jaguar.