I’m guessing the dogs didn’t like crazy Mohammad, because they sensed that he was a psychotic, murdering, raping, pedophile. Dogs are like that.
Thus, he declared that Allah had told him dogs are unclean.
They do intuitively sense nasty people of bad intent.
They also HIGHLY approve of bacon.
Dogs are awesome.
Close to the truth. When mohammad sent his 7 followers out to raid a village/caravan they would try to disguise (burkas?) themselves as one of the villagers or member of the caravan. But the dogs in the village/caravan knew who was a true member of their tribe and would bark a warning about the intruding mohammedans thus foiling their plans. To cure the problem of dogs ratting out the criminal/rapists in the village or caravan mohammad decreed dogs to be unclean.