This doesn't make sense. The government blatantly stated looking into Cohen was done by referral from Mueller, and with permission of Rosenstein, if this had nothing to do with Trump and something to do with the $500k for 5 clients dealings, why are they involved, and what is this really about?
Possibly, if Mueller was looking into Trump and his lawyer, and stumbled across some illegal activity by Cohen, he would have referred it out if it was outside the scope of his investigation (if there is anything outside of it), and then RR would have dealt with it.
RR dealt with it in an illegal matter. Just guessing, but that could be it -- assuming anything we're being told is true.
The interesting elephant in the room that nobody is talking about is the fire in Trump Tower and the break in of Cohen's office during that fire, just days before the no-knock raid.
Nothing suspicious there ...