The lesson of the Kobayashi Maru is not to 'listen to your crew'. It's to prepare future captains for the potential scenario where no matter what choice they make, something bad will happen. The burden of failure and loss are very real things for those who make choices that will affect the lives of others.
Kirk: How we deal with death is at least as important as how we deal with life, wouldn't you say?
When Kirk cheated on the test, he was ridding himself of its true meaning which would leave him mentally and emotionally unprepared when he faced that scenario with Khan. Spock knew the real meaning of the test because when the Enterprise was faced with a real no-win scenario, he was able to come up with a solution when Kirk could not. And Spock's solution had nothing to do with 'listening to your crew' since he told no one what he was doing. Even when Bones told Spock that he'd die if he went into the chamber, Spock did not listen.
I think the simulation in this episode did NOT need to be the Kobayashi Maru. It could have been any kind of simulation involving a tricky scenario that was, for all intents and purposes, winnable. I would even argue that having Dal do the easiest training mission first and being unable to effectively beat it would have better sold the idea of needing to listen to your crew. The Kobayashi Maru has a very specific purpose in the lessons it tries to teach which is not what this episode was about.