Well, I downloaded this filesee program that allows you to view files in a clear format. It seems that these hidden classes aren't in the scripts.rxdata file. The .rxdata file wasn't able to be fully read right, but I did manage to see the names off all the classes scattered in their order. Class Sprite, Tilemap, etc. were no where to be found.
I've looked in other files like the Game.rxproj, Game.exe, but my main suspicions is that it lies in the RGSS102.dll. Sadly, I can only interpret what it says in the least bit.
Wait....I think I found it!
It's VERY messy, though. I'm seeing things like "module RPG;class Sprite < ::Sprite;"
I'm interpreting the ";" marks as an enter space. OOOOO, this is SO exciting.
What I did is I converted it to Hex mode, then saved it as a .txt file. Now, there's large, script size chunks of coding. I'm gonna spend some more time with this. I'll clean up some of it and post it later.