They can file against you. But they have to prove that you were driving and under the influence at the time of the accident. The accident can place you at the scene and driving - if they don't have any other evidence. They can prove the alcohol by a blood test or urine test or breath test taken at the hospital. However, your attorney can argue that you were not under the influence at the time of the accident and that the blood test etc was done much later than you were driving - (for instance drank immediately prior to accident - blood alcohol had not risen to level of intoxication - but by the time they tested you it was at the legal limit.)
In short, yes, you can have charges filed against you even if you were not arrested at the scene. I know of one agency in my area, Clovis Police department, that does this.
Your question doesn't state that a chemical test was conducted. If no chemical test was conducted this will be a difficult case for the District Attorney to prove and I am suprised they filed the case.
If you have not done so already you need to contact an attorney to represent you. Just because you were arrested, doesn't necessarily mean you will ultimately be convicted.
It doesn't take much to be able to charge someone with a crime. The standard is whether there is probable cause to believe that a crime was committed. This often boils down to a judge listening to a police report. The only question at that point is: "if everything in the report is true, does that amount to a crime?" . This does not mean there is enough to find you guilty. Without other witnesses to your driving and an alcohol test, this sounds like a very weak case. It is good you found an attorney to fight this.
People who are not guilty and people who have valid legal defenses are convicted of offenses all the time. Without competent legal representation you could become or may have become one of them. From what you described, you should have retained an attorney before a bondsman. In California, on a misdemeanor an attorney can normally appear and get a warrant recalled without posting bail. If there was an accident with injury or three priors, the case could be charged as a felony. This would require your appearance, but bail can often be lowered. There are many potential defenses to the charges, including but not limited, to 1) the lawfullness obtaining your blood sample, 2) potential denial of speedy trial rights, and 3) a host of other defenses pertaining to the charge itself. Since your question petains to an accident on 11-01-2008 that you became aware of 6 months later, it seems that more has transpired than you have disclosed in your question. Since you said you talked to an attorney but haven't disclosed retaining one, you may not haveor have had the legal representation sufficient to protect your interests and assert all your potential defenses.
This sounds like a good case. Without a chemical test it will be difficult (if not impossible) for the prosecution to prove that you were under the influence at the time of driving. Get aggressive representation and you might just see this case dismissed.