A serious accident occurred before the operation got off to a proper start.
For whatever reason, the RA stealth cruiser got detected in advance!
This wasn't supposed to happen!
The Ghirard Fleet was predominantly made up of nunser warships. The other vessels originated from various vassal races that possessed inferior tech and capabilities.
Nunsers tended to be fairly unexpectional when it came to their technological prowess. Their scientists and engineers were not dimwits, but they weren't geniuses either. The puelmers easily beat them in this regard.
Since the rise of the Red Cabal, the major alien races had engaged in increased technology sharing and cooperative development. It was not impossible for the nunsers to obtain superior detection tech, but even if that was the case, the differences would have been noticeable.