During that period a runway incursion happened, with one aircraft taking off from a taxiway that was blocked on the far end by another aircraft. So it was rather a taxiway incursion.Nothing happened,
Nothing happened!
Using taxiways as runways when the proper procedures are in place is not that unusual, but allowing an aircraft to take off from a taxiway which was blocked by another aircraft at the far end would be grounds enough on it's own for taking severe disciplinary action against the ATCO who authorised the take off.
All three controllers were degraded, because one who was sleeping was entered in the position log. All three of them will never work as ATCOs in Germany again.
If the ATCO concerned was supposed to be operational but asleep away from the position, again it warrants disciplinary action.
Not only "falsification of documents" but also what appears to be gross negligence and possible collusion between the guilty partys to get their story straight.
Whether they all deserved to be sacked is debatable, but certainly the ATCO who authorised the taxiway take off should have at least lost their unit endorsements and be made to retrain at the unit from scratch.