It's me again. I managed to complete the details of all the 495 trainers in Pokémon Gold. It is a PDF document joined to this topic. (There's also the Excel file I made if you are more comfortable with that!).
It includes all the trainers in the order of the game, and sorted by groups as well (with their number in hex as well, so you don't have to count in the list all the time to know the number of the trainer!). Also, each trainer's flag is next to it, as well as their trainer data (Hex code) next to their name as well. It can be usefull if you wanted to change pointers or to rapidly find a specific trainers in the Hex code of the ROM.
I really hope it will be useful, coz really, it's usefull for me! Everything about the trainers are in one place now!