unlikely...

There are many methods in my controllers that have a specific param: $webinar_id
Most of the time it is the only parameter (but not always).

define different routes for the different conditions. so for example when webinar_id is not the only parameter -
then create a different route to pick up the other params.

otherwise you can check and validate anything you want in the controller constructor, and then redirect or whatever you need before the controller method is called.