But is he doing research? Has he read on the Cosmological Principle? Maybe some reading on what standard deviation (5.2σ on this paper) is and what it means to

But is he doing research? Has he read on the Cosmological Principle? Maybe some reading on what standard deviation (5.2σ on this paper) is and what it means to things being naturally random? How about reading the original paper? The Discussion section makes it very, very clear how the scientists reached the conclusion and how the Big Ring is statistically significant -- and in the process literally answering OP's question.