I used to think that conversation with Canderous was referencing something like the "True Sith" mentioned in TSL, but besides the fact that the conversation was not acknowledged in the novel, a closer look at the following quote makes me pretty certain that Canderous thought Revan and Malak had acquired their military capital (ships, droids, weapons, etc.) by allying with the rebuilt remnants of Kun and Qel-Droma's Sith "empire" (since he was unaware of the Star Forge at the time):
"The Sith had gone – retreated into their empire. They sealed themselves off from the rest of the galaxy. We thought it would be centuries before they'd come back. It's amazing that they could rebuild their fleet so fast."
If the Sith he was referring to rebuilt their fleet shorter than on the order of centuries, the only Sith he could really be referring to were Kun and Qel-Droma's AFAIK.
The stats posted earlier in the thread for Revan and the Exile are from the Saga edition KotOR campaign guide. Saga edition and Star Wars d20 (which the KotOR games are mostly based on) are closely related, but not the same, with some different rules regarding ability scores (for example, Saga Edition lets you boost two ability scores by one point every four levels instead of just one ability score).
Also, as I've been told countless times, while general character information in RPG sourcebooks is canon, character stat blocks (ability scores, feats, abilities, etc.) are not.
Nevertheless, presumably the RPG authors were working from notes and source material that result in a close approximation of what the creators of the characters envisioned.
RE: the novel
The novel hit on all the necessary plot points, but it really did so in a pretty generic fashion.
The entire novel is told more or less "over the shoulder" of the POV characters, just like it was a partial script for a computer game, and never "zooms out" to touch upon the state of the Republic, its military, the Jedi Order, etc. The Sith Empire the novel portrays is a starport, a couple of palaces/fortresses, a club, a cave, a factory, and a warehouse, with slaves, subjugates, and military personnel wandering about.
I don't know if the author was working on a page restriction, but the novel could have been a lot better with more time spent conveying the state of affairs and setting the stage for the war to come. The desperate need for Revan and the Exile to succeed in delaying the Emperor's plans because the Jedi Order needed time to rebuild and the Republic was still in shambles after the Jedi Civil War and its aftermath was never conveyed, nor was the terrifying buildup of the Imperial military.
I didn't really mind the depiction of the two Jedi heroes. For me the book left enough unsaid to allow the player/reader to interpret plenty of both games the way they choose.