Revan doesn't have the Star Forge, but he does have everything the Star Forge made. And something that I should have brought up in the Grievous vs. Revan battle was that a good portion of the capital ships produced by the Star Forge were Derriphan-class battleships that were used by Naga Sadow. These ships are not very good compared to what Xizor can bring. They are essentially useless here.
Wow that is a terrible ship...no shielding? A class 4.0 hyperdrive with a backup 12.0? The only thing good about it, is the concussion missiles but even then, Xizor's ships can be outfitted with point defense laser cannons(in fact some of them already come with those). If thats what a good portion of Revan's fleet is then...wow.