Older U3 devices lack support for Windows Vista and Windows 7. The only way to remove the U3 software is via a Windows XP machine. Support has told you the answer, you don’t want to accept it, but it’s the answer regardless, and complaining about it won’t change anything.
Libraries usually have machines with XP go to one of them.
Worst case return the Cruzer to where you bought it and have them remove the software or refund your money.
