You cannot share the same name with non-toggleable inputs. Radio and checkbox are fine as they require the same name in order to determine successful field groups. The hidden will be overwritten by the radio group following it. See your var dump results, you have selected accept for friendRequestDecision and friendRequestDecision.
So to answer your question, yes both get submitted. But only the latter one is successful. I'm not sure why you want that hidden field though; even if no option is selected, it would be presumable that you cannot pass a non-existent id into a query to update. If you cannot do that, than it is implicitly ignored.
So in other words, the hidden input is useless.
As of PHP 5.5, the MySQL library has been officially deprecated. It is recommended to move to either MySQLi or PDO libraries for your mysql connectivity. See here for help choosing which interface you prefer: http://php.net/manual/en/mysqlinfo.api.choosing.php