The MV cameras use the standard Meraki cloud connection IP addresses and ports. In addition it requires connection to compute and storage resources in regional data centers for video processing. These MV services use different IP addresses and ports to other Meraki products. If you have a firewall that drops outbound connections unless they are specifically defined, this will prevent your MV camera from streaming video as well as impact other MV related features.
The most current list of outbound ports and IP addresses for your particular organization can be found here.