In order to adequately respond to this question, it is necessary to review the documents which granted the right-of-way to neighbor 1. If the language allows neighbor 1 broad use of the right-of-way, that neighbor may be able to allow neighbor 2's use of it.
At the end of the day...what's the harm caused by neighbor 2's use of the right-of-way for this limited purpose. Even if it is a technical trespass, what are the damages attendant thereto?
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