That fighter looks like it could have been a Vasudan counterpart to the Ulysses. For example, the Uly was part of a joint Terran-Vasudan design effort, but it has more of a Terran feel to it. I therefore believe that Terran influences were stronger in the Uly. That said, its not unknown for new fighters to have fly-offs against another craft designed for a similar purpose. Take the YF-22 vs. the YF-23 as an example. Perhaps this fighter was in fact a result of the same joint design effort, but had more Vasudan design influences than the Uly, and the Ulysses won the competition, so this is kinda its competitor prototype. Perhaps the fighter itself found its way into a Mercenary collection of fighters. Granted, to look a bit more Vasudany, it needs some mild design changes, but nothing I can put my finger on right now.