Your link is talking about clusters of 15 or fewer people with extremely common forms of cancer like breast cancer.
That is incredibly different from this case which is 100+ people with an extremely rare form of cancer.
It's a good point that even if an individual cancer cluster seems improbable on its own, such clusters may occur by chance once you look for any clusters anywhere, but it's important to understand that this depends on the actual probabilities involved which are determined by both the number of cases and the type of cancer, so that is almost definitely not applicable here.
That is incredibly different from this case which is 100+ people with an extremely rare form of cancer.
It's a good point that even if an individual cancer cluster seems improbable on its own, such clusters may occur by chance once you look for any clusters anywhere, but it's important to understand that this depends on the actual probabilities involved which are determined by both the number of cases and the type of cancer, so that is almost definitely not applicable here.