Although I haven't seen any cases where this was related to template or virtuemart itself but more to do with email account type used in the users account, joomla mail settings, host mail protocols.
Try following tests.
As you are receiving notifications in super user account, for test purposes replace store admins email address with the one you have in super user. If this doesn't work then we can limit this problem to Virtuemart, if it works then either account type such as Hotmail / Gmail is the problem or your host does not allow automatic mail sending to these types of email accounts.
Try and let us know.
See you around...