Unlikely: There is no mention of where the arms have to be. So a pregnant lady can have 4 arms with one baby ( of course not at the shoulders ). Since the next person one meets is unlikely to be a pregnant lady, it is the answer in my opinion.
There is, of course, another event wherein a person with more than 2 arms could also meet him which is even less likely.
[Polymelia also known as hydra syndrome is a birth defect involving limbs (a type of dysmelia), in which the affected individual has more than the usual number of limbs.]