If he was really making something like $6 mil a week he has to have been the richest at the time. We can't know for sure, but even with all the other big money schemes going on and tribute they received I'd guess he was making more than the bosses. Even if he was giving Persico $2 mil a week.

And if he was giving Persico $2 mil a week, do you think that would bump Persico up to the richest boss at the time?