I'm seeing similar behaviour and when files are deleted the preview of the returned file shows "The operation failed because Shortcuts couldn't convert from Text to NSString."
https://s3files.nyc3.digitaloceanspaces.com/ScreenRecording_09-17-2024%2020-32-46_1.MP4
My work-around has been to rewrite the SiriKit intents into AppIntents which requires @IntentParameterDependency and iOS 17 but because of weaknesses in CustomIntentMigratedAppIntent this makes the existing SiriKit intents unavailable to users on iOS 16:
https://developer.apple.com/forums/thread/734252