The number-letter switching condition of the DKEFS trail making test is actually the one most diagnostic of EF skills, and suggests a significant challenge in this area, especially in cognitive shift (adaptability, flexible thinking). I would suspect that EF concerns are indeed affecting his performance in school, as well as (likely) his access to effective social and emotional problem-solving strategies--which in turn contributes to conflict particularly in his closest relationships.
A diagnosis can be helpful, but the more important take away from this eval is that he presents with significant personal and normative weaknesses in changing strategies when his attempted solution to a problem (of whatever nature) is ineffective. My experience with this quality in a cognitive profile is that they tend to get stuck, and dig in their heels when confronted with conflict, which just escalates the situation. They often need to be taught how to deescalate their own emotional reactions, and then apply strategies to "back out", analyze the problem objectively, sift through, and then select and attempt multiple alternate solutions.
