Did you turn the option off in email gaurdian first then remove your email from the list? then uninstall it.
ive had quite a few spam that showed as safe but ive never bothered turning it of in UI.
so just turned off and sent test email and the green safe tag has gone.
Im guessing if email gaurdian does not show up on your UI then youve not removed it correctly.
hopefully a techy may be able to advise further.