Fiance deploying, we want to get married before he leaves. His final divorce papers won't be in until he is gone. Is there anything that we can do?

No.  It's what lawyers and judges call a "bright line rule," that if a person is in a legal marriage that has not yet been dissolved by a signed and filed court judgment, any later marriage ceremony that person is in during the original marriage is absolutely void, as if it never happened.

There's just no way around that.  You might want to look into whether you can get legally married, after the divorce, "remotely," over a teleconferencing system.  It's been done with older technology, or so I've heard.