As a former DA who handled these types of cases, the first piece of advice I would tell you is to call the Los Angeles County City Attorney and get a victim advocate. The victim advocate will be able to keep you updated on the developments in the case and will know what the status of the case is. Often times you can make an appointment to meet with the victim advocate, investigator and prosecutor assigned to the case. This helps in that you are able to make sure all the facts are discovered. The City Attorney can only go forward on a case where they have the evidence to prove beyond a reasonable doubt, so the ultimate decision of how to prosecute the case lies with them. I hope justice is served in your case and that you contact a victim advocate at the City Attorney's Office.
If your attacker is not a citizen, the City Attorney may not be filing the false imprisonment/kidnapping charges because if he were to plea to them they do not have the disasterous immigration consequences that a plea to 242 or 243(e)(1) would have.
If he were to plead to false imprisonment w/o violence or fraud that would not be considered an aggravated felony. Anything in the assault -- battery section of the penal code would certainly be.
Edward J. Blum