Pokémon Colosseum Gen 2 Starter location

[Muckifant]

So i want to rng for a shiny Bayleef in Pokémon Colosseum for a ribbon master mon.
The best spot for that is supposed to be in the snagem hideout since this is the location with the least noise out the other two which are Phenac and the Shadow lab.

But does anyone know what actually determines and when, which of the gen 2 starters appear in which location?
I know it's random. I played through the game twice now and caught Quilava in the first pt and Croconaw in the second (In Phenac).
Both times i was unlucky and did not get the Bayleef Trainer to appear in the Snagem Hideout.

What i am looking for is basically a way to abuse for the location itself or a way to take a look at a specific part of my save file to know where Bayleef is going to appear or something like that.