The referees have owned up to getting the call completely wrong and have apologised to the Bayreuth Tigers (not that they can buy themselves much for it).
The main ref explain the decision as follows (slightly Paraphrased):
"The Crimmitschau player shoots and I noticed something black hit on the inside of the far corner. I decide on goal. The Crimmitschau players are happy and there is no objection from the Bayreuth players or bench staff. Only in the intermission did Bayreuth and we (the refs) learn via phone call that it wasnt a goal."
One of the linesmen also stated that when he saw the puck inb the corner he didn't necessarily think it was out of the ordinary since its a regular occurence that a frustrated goalie or defenseman clears the puck from the crease.
Link
Curious and somewhat baffling situation nonetheless ...