question

On the basis of your workaround, you can add the server logic to prevent the “empty” item from being granted to players. As the documentation says, you can use this Server API method EvaluateRandomResultTable on CloudScript to get the result of an evaluation of a Random Result Table. So you can add the processing logic for “empty” items in the CloudScript functions. Please refer to the following testing function.

handlers.EvaluateTable = function (args, context) {

    var evaluateTableResult = server.EvaluateRandomResultTable({
        TableId: "Test Table"
    });
    var itemId = evaluateTableResult.ResultItemId;

    if (itemId == "EmptyItem") {
        return "Granted nothing."
    } else {
        var request = {
            PlayFabId: currentPlayerId,
            ItemIds: [itemId]
        }
        var GrantResult = server.GrantItemsToUser(request);
        return "Granted " + itemId;
    }

}

For clarification, as our documentation says, the API methods about Drop Table can't be called by clients directly. The sample code shows a workflow that automatically granting all the result item. So you can add a condition judgment to prevent the server from granting items whose name is "nothing" or "EmptyItem".