Does the Olympus software even launch? In addition to @kaz-k's suggestion you can Control-click or right-click the app and select "Open" which will warn you and prompt you whether to allow the app to run if the software/developer is not recognized by Apple.
If the Olympus software does launch, then you may need to provide it permission to access the Downloads folder or to allow access to your Olympus camera. Check this under the "Privacy" tab in the "Security & Privacy" section of the System Preferences.
https://support.apple.com/guide/mac-help/change-privacy-preferences-on-mac-mh32356/mac