The problem that I have with some fan fiction is that the author in most cases misses the importance of the Starbase 1 in FJ's technical manual, and the super Phasers...
Vanguard should have been able to destroy the incoming Klingon Fleet, with ease.
Meaning that Vanguard shouldn't have been destroyed at all. The Klingon Fleet? Toast. Gone. No longer in existence.
No excuses.
Using my favorite resource 'The Star Trek Spaceflight Chronology', standard Phasers would have gone through the Klingon Starships deflectors without difficulty.
Fireship(s)???
Going to FASA sensors and Tricorder supplement...
The FRB sensor system, would give the Klingon KRA sensor system fits.
Klingon sensor systems are designed to detect opposition ships, and secondly to detect natural hazards. On the hunt. (STAR TREK THE MOTION PICTURE)
When David Gerald wrote about Star Trek, so long ago, he said to think of Klingons as the Mongolian Hordes...
Such that the the Klingon Bird-of-Prey is a valid idea. But not necessarily in that configuration.
Instead of calling it a 'scout', call it a "spoter"...
Errand of Mercy.
Deeper dives are required.