I asked aldelaro and he doesn't remember if it was made with US or JP in mind but he thinks it was US. Also he linked me to this, not sure if it's any different from what you were using
https://github.com/aldelaro5/dbzLog2StatsRng
I will say that on our first TAS, we def waited slightly at the beginning for Trunk's stats. That's kind of surprising if ASDQ didn't at all, I assumed they just didn't bother editing the overlay for such a short section of gameplay. I should really try to load it back up and see what the values were at each point... There was some stuff you could do to change RNG drastically by punching or shooting Ki blasts into cutscenes. For Piccolo, we ran into him to make the screen shake which changes RNG a bunch every frame and happened to give a good result. I think it was the equivalent of waiting like 12-13 frames or something?