I know someone from the U.K. who worked at WDW for a year and lived with roommates who worked over at Universal. Whenever he’d have a day off and headed over to Universal, he could always get through the express lines in both parks by using the phrase ‘Sal from forbidden journey said I could come through’. This was from a few years back now, so not worth trying at this point I would imagine, but he said the code was always the same. The guy Sal was apparently one of the team leaders who worked on FJ at the time, the boss of one of his roommates basically.