Fyres of the house of Orca was a wheeler-dealer, who (after two previous failed attempts) parlayed a single unfulfilled contract for 5 Man'O'War ships for the Empire into a convoluted series of loans taking other loans as collateral, and shell companies without assets, until he appeared to be extremely rich and successful. Unfortunately for the Empire his loans were all bad ones and required further loans to support the payments. By the time this was discovered, the amounts were so large that exposing the true state of affairs could bring down several major banks including the Imperial Treasury itself.
His untimely death threatened all of these consequences and more, so the Empire was anxious to keep his death and financial situation as quiet and un-investigated as possible. Those who knew about the Empire's reluctance to know conspired to profit from it.
In truth, Fyres' death was not an accident, it was a murder, as a part of the conspiracy, carried out by the agents of Stony