Well, thanks to Irfeir's help at the Skyrim CK public chat in Steam I figured it out. The solution to the quest adding it every time the save is loaded was to nest every formlist.addform(form) inside an if !formlist.hasform(form), to check if the formlist didn't contain the form, if it didn't, add it, if it did, do nothing. Then to uninstall it, to prevent the forms from staying inside the formlist after the plugin/master is disabled, I created a spell to stop the quest, check if the forms are there with formlist.hasform(form), remove every added form from every formlist with formlist.removeaddedform(form), and show a dialog saying it's safe to remove now. I hope this helps people adding stuff to formlists dinamically in the future. If it works with voice types, it should work with mostly everything else. Good luck.