Based on the information that's been reported, by definition the crime isn't Murder in the 1st degree or Capital Murder in Virginia so it's not really a matter of being proven. Based on the facts it will be a matter of Murder in the 2nd degree, Voluntary Manslaughter, or Involuntary Manslaughter.
The most sympathetic set of facts for the accused (the catfishing scenario where they didn't know the identity of the deceased until the second encounter) could result in a Manslaughter conviction. In my opinion, there are several more likely sets of facts, most of which would lead to a Murder in the 2nd degree conviction.