When you rename a MetaSound input, every Set Parameter node, Spawn Sound chain and audio component default in your Blueprints keeps setting the old name. Nothing errors or warns, and the sound just stops responding.
MetaSound Parameter Surgeon is a commandlet that rewrites those Blueprint setters after the rename. It decides from the assets which sound each setter drives, rewrites the ones that belong to the renamed MetaSound, leaves the others alone and lists anything it cannot decide. Every write is journalled and can be undone. It does not read Level Blueprints yet. The code is AI generated. It costs $14.99 on itch.