Restoring the texture of Renegade Knights from Hammers of Fate.

The thing is that a hero "consists" of several parts: a horse, a body, a flag, etc., and there is a file describing each part... Perhaps you extracted the ID from the "wrong part."
The description of the geometry, as you call it for the "Renegade Knights," is stored in Characters\Heroes, and for all heroes of this type, these files are the same, meaning you don't need to change the geometry for each hero.

Renegade_Hero_LOD-geom.xdb
Renegade_Hero_LOD-geom-AI.xdb
Renegade_Hero-geom.xdb
Renegade_Hero-geom-AI.xdb

These files contain the IDs you need; I just checked.

By the way, I noticed something: in the hero window, all characters from Haven are displayed with weapons, but on the map, they are displayed with a flag. Is it the same with Hammers of Fate?