A temporary DV order is made based upon the written declaration of the petitioner and nothing else. If the facts are materially false, you can, not only have the order dismissed, but you can request sanctions against the petitioner, under Code Civ. Proc. 128.6 and 128.7, for attorney's fees, costs of suit and to discourage future frivolous conduct.
Your husband would have had to provide you with 24 hours notice of the ex parte hearing from which the DV order was issued. Not doing so, is also sanctionable, and lying about it, like lying on the attached declaration, could be prosecuted by the district attorney as perjury.
BotXXXXX XXXXXne: if you go to court and testify that your husband's declaration is false, then the judge may just "throw the book" at your husband.
However, between now and the date of the hearing, your son must stay away, because he can be arrested for violating the court order -- even if it is later dissolved in his favor.
I STRONGLY recommend that you and your son each get a lawyer to represent you at this hearing. For a family law attorney referral, see: http://www.abanet.org/legalservices/lris/directory/main.cfm?id=CA and www.martindale.com.
One more note: there are a lot of experts here who are not California licensed attorneys, and who will purport to understand California law. Be very careful about accepting their answers, unless they cite the legal authority for their contentions. California law is much more complicated than any other jurisdiction in the U.S., and I cannot tell you how many times every day, that I read an answer from a non-California lawyer that is simply wrong.
Hope this helps.
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