are there any locals on your campus you could merge with?
A similar situation occurred on our campus with one of our nationals. If they failed and charter was pulled, we weren't allowed to bring another national house onto campus for another 3 years. Only I think they were a lil worse off, they had about 9 members... house total is about 70 on our campus.
They got permission from their headquarters to recruit/COB for the entire semester they were having problems. Panhellenic also excused them from certain events and meetings that required 80% of the house to go and stuff like that. They asked other sororities in PHC to "recommend" the sorority. They also asked us to block rush, which they had before. We didn't feel merging would be something beneficial for Chi Delta in the long run. Lots of drama and complications. Don't really want to get into it.
But if there is a local on campus that has fairly decent numbers... 30 or so... ask them to merge. It would at least be some numbers for you.
Wear your letters like crazy. P.R P.R P.R! That's key as well.
Is this the first time that national has threatened you? If it is, be on alert but don't get too too worried about them pulling charter. The national that wasn't doing so hot on our campus had been threatened to have charter pulled since 1999. They recently initiated 21 girls within the last year and they finally got permission to participate in formal recruitment. Keep your head up and keep smiling.
Gosh... it's amazing to realize how big the greek system is at other schools. 45 members on our campus is fairly decent in our eyes. Of course, so is 65
Good luck