The key is not used because these requests do not require a key.
But, I think you're right, and the request should be registered.
A modified script is attached.

- https://developers.google.com/maps/docu … view/intro
location can be either a text string (such as Chagrin Falls, OH) or a lat/lng value (40.457375,-80.009353).

Just checked location requests, and on my side it works correctly.
Please send a location that does not work for you.

How exactly do you make the request?
Using Online Maps, Google Street View component, or API?
If using the API, please show your code.

The key is not currently used in the request.
The key is present so that when / if Google updates access points, we can easily update the asset without the need for users to modify their code.

        public GoogleStreetViewMetaRequest(string key, double longitude, double latitude, string language)
        {
            string url = "https://maps.googleapis.com/maps/api/js … c_._dqzs51";
            url = string.Format(CultureHelper.cultureInfo, url, longitude, latitude, language);
            WWWRequest request = new WWWRequest(url);
            request.OnComplete += OnRequestComplete;
        }