Again, this paper just looks at the correlations, and does not touch causation at all. You can run a hundred studies, each of them finding high correlation between wet streets and having rained recently, but you cannot conclude from that that the wet streets caused the rain to fall.
Hi, all causation can be doubted- that's a key aspect of skepticism, and in general, is important for philosophical development. In this case, it's clear that it is not a substantive objection to these papers or others. It is clear that you have set out this discussion with prior belief and are trying to reject that wealth disparity drives crime. You're not acting in the spirit of skepticism (and only are applying skepticism selectively here, because you think it sounds smart).
Read the papers. Apply your logic evenhandedly. Follow the leads and research on your own. It may be scary- you may discover things that force you to change your life (or you may learn something about yourself you dislike).
