Reynard wasn't a fool, and similarly, those military leaders of Hamlet weren't fools either. Could they not know that cavalry aren't heavily armored knights? Could they not know the characteristics of the Skeletons? If they were really to charge directly, it would only send them to their deaths.
The Lord's teachings were very clear: no matter what battle you fight, you must leverage your strengths. So what was Hamlet's advantage?
Clearly, it was these gunpowder weapons. Although muskets weren't very effective against Skeletons, bombs could cause tremendous damage amidst the dense, non-dodging Skeletons.
This was also why Reynard dared to take such a big risk and persist in advancing even under the circumstances where the black mist blocked the sun and the fog cut off visibility.
If charging doesn't work, then just blow them up. It doesn't matter if you can kill the Skeletons, as long as you disrupt them.
