To make an experiment to replicate the result again would mean sacrificing one or two rolls, and I am not sure it is worth the hassle. For me it is more easy to make a rule for myself not to develop agfa aviphot derived films in xtol, but to use rodinal or a traditional pq/mq developer instead.
You don't need to replicate the experiment. If the question you want to answer is simply, "Can Xtol be used to process Rollei Superpan 200 film?" then all you need to do is to expose some of your Superpan and process it in Xtol. If you are loading your Superpan from a bulk roll, then the test roll can be a short one.
If you are able to find the leader from the "totally blank" roll of Superpan that was previously processed, and if it is black, then you already have your answer. If it is clear, then another roll needs to be tested.
You could just, "make a rule for myself not to develop agfa aviphot derived films in xtol," but it would really require very little time and effort to find out the truth, instead.