No, he wants to know where in ZH the references to load data from the regular CnC Generals directory are contained.
To answer the question, I don't believe they're available outside of the hard code. Certain things are just plain loaded from Generals, ZH, or both dependent on what they are.
Suppose I wanted to change the in-game music, if I made a reference to an MP3 file in the ZH\Data\Audio\Tracks folder to replace say... USA_01 (which exists in the original Generals folder) then would it look in the Generals folder for the MP3? Or the ZH folder? (if it didn't use the existing filename)