CleanWipe isn't so clean - still requires uninstall password for orphaned SEP clients

I need a solution.

I have noticed the only clean way to upgrade a SEP 11 client from, say RU4 to RU7 is to

1. Run cleanwipe

2. Do fresh install of RU7

Here is the problem - when we send out technicians to run cleanwipe on an ORPHANED SEP 11 client, it asks for uninstall password, which we are not allowed to give out. And if technician does Add/Remove program, it also asks for SEP 11 uninstall password even though this is an ORPHANED SEP 11 client.

How to run cleanwipe on an ORPHANED sep client without providing password. Or, is there a workaround, such as deleting certain registry keys? From there, we can install later version of SEP 11.