You can change secure attributes in combat, however only in under certain conditions (everything that a macro can do), and you can only access certain functions in the
restricted environment, and you can only access your own secure references that you can only set out of combat and while logging into the game, or if your secure reference is a frame you can only access it's sub-methods limited too. UnitName() which would be the handler here for the changes you want to make, is not accessible. So it's not possible.