RE: *Using Threadlock*
I'd use a soldering iron to heat it up. You might also take a dremel cut off wheel and carefully cut one of the slots a little deeper and widen it across the bolt head to get a large straight slot on it. Red locktite is for permanant installations, next time consider blue.
I would make a straight slot, heat the bolt carefully with the soldering iron and see if you can break it loose that way.