What made you passed was the copius amounts of fluids youve drank (in the hours leading up to the U/A), which diluted the THCA concentration that was present in your bladder to where the urine sample registered below the cutoff thresholds of the drug screen. The jello mix played no role in making you pass. If your story is indeed true, you wouldve passed anyway just on the fluid-loading alone and without the jello mix to go with it.