The features tied to each should be listed in
Code:
/usr/local/cpanel/base/frontend/paper_lantern/dynamicui.conf
That said for just SSL/TLS (manually installing certs) the only feature that controls it is "sslmanager".
For the SSL/TLS Wizard (interface which allows you to purchase certs) it requires "market && tls_wizard && sslinstall" and has an additional check to see if "$market_has_enabled_providers" exists (basically if there are providers available).
If these solutions don't work for you, you can customize the dynamicui.conf for your users and add an if statement to the corresponding feature although to be honest I don't remember offhand if this requires cloning the theme which might be more than you want to do. Let me know if you have any further questions.