Inactive mysteinberg accounts, transfer licence

Hi, we currently run cubase 7 at my school and have 3 defective dongles we want to replace, we are unable to locate the activation codes as the school has had a rebuild and think they have been misplaced. We believe they were registered under a mysteinberg account of the IT manager at the time who has since left, is it possible to obtain the activation code from steinberg we have the products for each version?
or are they able to access the old steinberg account?

If you contact them, Steinberg Support can access those using the USB dongle serial number.