you could work around that by adding custom hostchecker policies. e.g. like that:
- create a rule for the service that norton runs via: Endpoint Security -> HC -> Policy -> "Add custom rule: Process"
by that you ensure, that the process is running and active on the users machine
- create multiple rules for different files via: Endpoint Security -> HC -> Policy -> "Add custom rule: File"
this helps you to check for various files the Norton Security Suite Software version 3.8.0.41 installs. so you could check if the norton software is installed, by looking for those files on the clientmachine.
you could also try to find the antivirus definition-file(s) and check with the "File modified less than: xx days ago"-Option when the last update of the definitions was performed! like: "if the file wasnt touched for 20 days, its not up2date and gets denied". so you would almost have the functionality of the normal antivirus check. (you have to be sure that the definition-file is not getting touch by any other application though ;-) )
you could also add registry keys or whatever, so hopefully this helps. if yes, please kudo me 
br
