a)…” the engine cowls from both International Aero Engines V2500 engines separate and fall on to the runway”
– not one cowl but cowls, from both engines. A highly remote co-incidence?
b) then…”In 2008 the NTSB issued four safety recommendations to the US Federal Aviation Administration in relation to engine fan cowls coming off, including concerns over fastening of the cowl latches after maintenance.“
– several links to this were also provided by Guest Poster in another thread.
Given that a bird strike was not mentioned, the remaining alternatives become increasingly likely – basic probability theory.