Well, let's see. First he missed hearing the "59" of 5912. He missed the word "emergency". When he asked for clarification of the flight number, he again missed the "59" of 5912, although it was even more clearly said by the pilot. Then he assumed that there was no such flight, without looking to see if there were any flights ending in "12", and concluded that it was a bogus call. Then he tells the pilot of 5912 to exit the runway expeditiously. Then after the admittedly pretty excited pilot said that they were evacuating the aircraft on 34, he asked "5912, confirm that wasn't you?"
The controller didn't have the pieces of the puzzle because he chose to disregard the pieces he did have.
Not wrong? Hmmmmm.
Cary