No our National organization can't colonize without the "proper authority" ie campus request or panhellenic request.
Check out
www.npcwomen.org, I believe that is the correct website for NPC, they have the rules of expansion on there.
Just because you can't work with a chapter doesn't mean you can't volunteer!! There are plenty of positions that involve day to day stuff that HQ needs people for. You know like writing for the Triad etc. Don't let the fact that there isn't a chapter around stop you!!!