Thanks Erich, yes, I have an SWD connection. I have a P&E Multilink for the debugger. Closest thing I have is in the debugger window in MCUXpresso there's a checkbox for "Emergency Kinetis Device Recovery by Full Chip Erase", but it's not responding. I'll see if the newer versions of P&E's flash programmer maybe have an option to try to restore it, but it can't even connect with the version I have.