Yes, you can use Symantec Network Access Control (SNAC) to ensure that any process is running and any file or registry key is installed on a machine, using a custom rule.

SNAC is built into every SEP client, and you enable the feature at the Manager level.

You can use the stand-alone version of SNAC combined with a quarantine firewall policy to not allow any of your client machines to communicate with the production network unless SNAC finds that DLP is installed and running.

An Enforcer Appliance or the Integrated DHCP Enforcer allows another layer of protection, as they enforce the policy before the machine can get access to the network, which prevents rogue machines or machines that have had SEP disabled/not installed from entering the network.