Thinking outside the box here -- why not just set up a bank? It might not be easy, but given the amount of capital floating around in crypto land, I assume it should be a non issue.
It's very hard to get regulatory approval for a banking charter right now. The FDIC has been approving less than 1 new bank a year since 2009, as compared to an average of 154 a year in the eight years prior to 2009[1]. And that's just one of several regulatory bodies that would need to approve a crypto bank.
There might be shell companies with a remaining active banking license, that were approved pre-2008? Seems like regulators are preferring that you acquire a charter over acquiring a new license.