The biggest problem is that Alexander’s plan is dumb from the ground up and dumb from the roof on down the other side. To make matters worse, it’s badly executed. The detail of the extra character on the d’k tahg was an obvious problem, but it’s also obvious that Alexander never expected the sisters to be found. That, however, points up another problem: Alexander lived on the Enterprise. He knows exactly how resourceful this crew is. Why would he be surprised that they’d go after Lursa and B’Etor or that they’d be successful? And while seeing “K’mtar” aim his disruptor at himself makes for an impressive image, on what planet does killing his younger self make sense?
Then again, Alexander was a dumb kid, makes sense he’d be a dumb adult.