FMOD Studio scripts are only effective within the FMOD Studio application, and cannot be used in-game. (Well, not without using live update, but I assume you don’t want the FMOD Studio GUI running in the background whenever your game is running.) This is because the scripting feature is designed to allow you to simplify your workflow by replacing time-intensive multi-step procedures with keyboard shortcuts and menu commands. It is not designed to allow you to trigger and control the content of your project, as the FMOD Studio API already exists for that purpose.
For the same reason, it is not possible to trigger an FMOD Studio script from an event or snapshot, as such a trigger would be meaningless in-game.
In addition, it is not possible to replace the impulse response used by a convolution reverb effect as your game runs. This is because the impulse response file is built into your project’s master bank as part of the bank building process. A better option is to create multiple different convolution effects on different return buses, and use snapshots to determine which of those buses receives audible input.