i'm sorry, but your lawyer should be able to find a way out of this.
legally you should be allowed to see your files (blacking out the names of the people who filed it of course). also, the humane society would have you on their records if you ever adopted an animal from them. so in the process of investigation they should have found that you have never adopted from the OHS.
If the file against you is outright lies (multple animals, eg) then the SPCA investigation should also uncover that.
i agree that you should get the media involved. more attention will create more sympathy from the public and will turn the SPCA on their heads trying to figure out the truth.
i would try and press for more time to investigate, because honestly it doesn't really sound like they have done their homework on you. plus, your landlord sounds nice and is obviously willing to let you keep those animals. moe time= less stress= possibly being able to keep your lovies.
i would really like to help with your animals but my roomate is pretty allergic to animals, but if you get really stuck PM me and ill see if i can work something out.