Are your telling me that folk selling this service are not answering questions about their product? That's a sure sign you don't want to go with that company.
You've found a great question for your prospective hosting server company to see if they will support your needs.
I've never used a hosting server before.
Is it possible to have the access locked with password under the cPanel? So that even if there were multiple manager logging into the server account, some of them still wouldnt be able to manage some certain web sites?
And of course I'm just asking.