The female prison worker questioned as a possible accomplice in the escape of two killers is a married, training supervisor at the facility, sources told The Post on Monday. Joyce Mitchell has worked at Clinton Correctional Facility since 2008 — and her responsibilities include helping inmates learn how to tailor clothing, the sources said. Sources said Tuesday that convicted murderers Richard Matt and David Sweat were allowed to wear civilian clothes instead of prison greens in their less restrictive wing of the jail dubbed the “Honor Block.”