What do you mean by adding to Meraki MX?
MX is a firewall/router; you don't manage cameras through it.
Now, you want to manage third-party cameras in the Meraki panel, but that's not possible.
I am not a Cisco Meraki employee. My suggestions are based on documentation of Meraki best practices and day-to-day experience.
Please, if this post was useful, leave your kudos and mark it as solved.