I do not think they will go to Valhalla either. I believe that they cease to exist even in spiritual form because it was such a terrible battle. It is like the Norse form of the Christian battle known as Armageddon, except the so-called gods were not very powerful. So, nowhere. They ceased to exist. They went to a place known as Ekkitil, or Ekkaia, as it is usually known.
Those who die remained in a spiritual world awaiting judgment day. Germanic people perceive Ragnarok as the end of the old world. There were survivors of Ragnaro, for instance, Odin's brother Honir, Odin's sons Vidar and Vali.