Create a signed URL with a four-hour expiration and share the URL with the company.

Set object access to ‘public’ and use object lifecycle management to remove the object after four hours.

Configure the storage bucket as a static website and furnish the object’s URL to the company. Delete the object from the storage bucket after four hours.

Create a new Cloud Storage bucket specifically for the external company to access. Copy the object to that bucket. Delete the bucket after four hours have passed.