Considering RUN wasn't designed past 70 this doesn't surprise me. You are also unable to level RUN or GEO as your first 75 job (now first 99 job). Currently RUN and GEO are capped at 70 unless you have a previous job at 99 already then you have no need for the quest and are able to go all the way.
I think if you just drop the trial weapons it gets interrupted since it's related to that. If you have the annal of truths though I'm not sure you can interrupt without going to kill the NM and then reporting back.