VideoNFTizer Agency Upgrade adds the following 2 major features in your account:
1. Allows to deploy unlimited contracts for unlimited collections.
2. Ability to add up-to 5 Subaccounts.
So the best way to check if your VideoNFTizer Agency upgrade is active or not is to check if you have access to Subaccount creation in your account.
So simply login to your VideoNFTizer account. On the left hand side menu look for Subaccounts link below AGENCY. If you have a Subaccounts link, your Agency upgrade is already active.