How to do a full backup restore with Snapshots

I am running a multisite and am using Snapshots. Currently, I have snapshots set up for the primary domain and all subsites.

If my whole site goes down, and I can't even get to the Wordpress dashboard, is there a procedure for restoring everything?

Or, let's say that I can still access my main dashboard, so I have to restore every site separately, or just the main domain?

I can also get a full backup from my host, so that would be the fall-back safeguard way to restore the site, right?

I'm just wondering how much I can depend on Snapshots in the most severe case of no access to the Wordpress dashboards.

I use Updraft Backup plugin on other non-multisite projects. Don't know if it would work to back up my entire network. Do you recommend any other plugins that might backup everything and be able to restore everything from either the Network admin or the primary domain dashboard?

Thanks, Joe.