Any ability to change SurveySession results after the customer has completed their Survey?

Summary: Changing Survey results on SurveySession

Content (required): Sounds like my boss wants to fudge the numbers but its not for me to judge :D So anyone have a clue, seems I can query the results via ROQL but I cannot fetch the objects via the Connect Common Objects Model.

Version (include the version you are using, if applicable): 19D

Code Snippet (add any code snippets that support your topic, if applicable):

Theoretical concept

$surveys = RNCPHP\ROQL::query("SELECT * FROM SurveySession WHERE Contact == 30")->next();
        while($survey = $surveys->next()) {
            $survey = RNCPHP\<???SurveySession???>::fetch($survey["ID"]);
            $survey->CustomerHappyiess = "EXTREME";
            $survey->save();
        }