The issue appears to be with your actionPerformed script on the Delete Email button. You do not need to add single quotes around the string values for EmailValue and EmailRole, the runPrepUpdate() function makes sure those strings are properly passed to the DB. So remove these lines:
EmailValue = "'"+EmailValue+"'"
EmailRole = "'"+EmailRole+"'"
And you should be ok. Adding those single quotes will search for the literal string with the single quotes attached, and naturally, none of the emails in your table will have those single quotes added in, which is why the delete query wasn’t doing anything.