This was never intended to subvert דינא דמלכותא, however as we see דינא דמלכותא go down hill to דיני סדום, was trying to see if there could be a legal setup that would make it possible. From what I gather thus far, in NYS it's probably impossible (still waiting for clarity on whether a מודעא as I suggested above, would have any legal standing, and possibly a domestic partnership filing in order to establish that there was no intent to establish a civil union). It does seem at the moment that in NJ one can be halachically married and not civily married.
Just to give a little background as to how the seeds of this idea were planted in my head. I am licensed to sell health insurance in NY. When Obamacare came about, I had to attend a special course in order to be able to sell on the NY health exchange. It was that course and the perverted case scenarios we had to answer questions on, that got me thinking on what might work for the Jews. All within a legal framework.