Wrong users added when creating new site in network

Hello, one of my clients have a problem I can't seem to track down:

The setup is a network install that has 10 superadmins that create sites. Its a network that sells simple websites, and these 10 superadmins are like designers, they get assigned a client and they go ahead and create an account for the client.

What should happen: each superadmin has his/her own account, which they use to create a new site via Network -> Add New Site. When they are logged in with their account, they create a new site and assign a name for that account. So far so good. When the site is created, the new site is created with the username they entered.

Now, what sometimes happends is that when they create a site, the wrong username gets added. Could this be because they are creating a new site while logged into the admin panel of another site account?

So it goes like this: SuperAdmin1 is logged in and goes to Network -> Create site, and adds a site SiteA. The new site is created with the username SiteA. But sometimes they add a new site, and it gets created with username SiteB. Is this because they are logged into SiteA when they go to create a new site?

The designers usually have multiple tabs open, with several user accounts open. I guess this is where the problem lies.

Sorry for the terrible explanation, but I don't know how to explain it better.