Can you try check your mail activity from backend > Easydiscuss > mail activity and see is it all the email notification still under pending status?
If yes, It seems like you haven't setup the cronjob in your server yet.
If no, It might be your Joomla mail setting is not configure correctly. If that is the case, can I have your Joomla backend and FTP access so we can better have a check on this? Because by right it should notify to your Superadmin/moderator to know have new post under moderation.