So, in my book it has nothing to do with identifying a taxyway from a runway, but more to do with not apparently realising that the "real" runway was back in operation. The question is: why?
Avman, a NOTAM was issued to inform about the change. I guess waiting to be in short final to discover the news may be a little too late.
Moreover, in case of doubt GA and come back. Unless internal policy discourage this practices.