Dale could very easily have had an accomplice (knowingly or unknowingly). I believe it is VERY feasible. IMO Dale has many shady friends and I still question the circumstances around his second wife's death. His second wife's family believe Dale somehow was involved according to what I've read. His second wife happened to die around Dale's friends? Come on now!
As I recall, KC, like Dale, refused to answer LE questions. As I ALREADY mentioned JMO this COULD have been a heat of the moment, crime of passion involving an accidental death or murder. But I still believe he had a plan in the back of his mind (not sure how well planned or detailed, but I strongly believe he knew he was going to do this one day).
Dale already had two strikes against him. FL is a three strikes state, isn't it? Maybe he took something too far and knew he needed her quiet or he was going back to jail? Whether it was planned or unplanned, I believe once whatever happened took place, he needed some help (rides, moving vehicles, getting rid of evidence). I have extensive theories on how he COULD pull this off with and without accomplices. I will respectfully keep those private...