'quite murky' is a correct and usable phrase in written English.
You can use it to describe a situation that is unclear, mysterious or dark with regards to a particular matter. Example: The circumstances surrounding his sudden disappearance are quite murky.
Ukrainian politics can be quite murky.
Right now, though, the specifics of who will feel the cuts, and when, are quite murky.
It did cross my mind to buy Japan and give Japan to the nation, but my accountant has informed me that the legalities involved are, unfortunately, quite murky.
"A lot of the deals that took place were quite murky," said Kane. "We are not used to individual land ownership here".
"It has astonished me that what had been a fairly clear provision in a standard lease has now become quite murky," said Sherwin Belkin, a Manhattan lawyer who represents landlords.
The notion of self-ownership invoked in this argument is quite murky though.
What is quite a bit murkier is the exact sequence of events, because the body was found to have a broken neck, doubtless the result of the fall.
As things turned out, they received, at enormous expense, something quite different – a murky-brown, socially conscious western (exactly what the executives didn't want, and had kidded themselves they weren't getting) about a war between cattle barons and immigrants in 1890s Wyoming.
By now the rash is almost, but not quite, receding into the murky realm of Weird Things That Happened Once (and Most People Gave Up Trying to Explain).
The underwhelming air is compounded by the fact that an undeniable single along the lines of 2013's Versace or last year's Fight Night is noticeable by its absence: One Time comes closest, but its hook doesn't quite cut through its murky darkness.
It's a great place to bone up on the world events you have heard about but never quite understood from sketchy, murky news accounts.
