When you say "These subsequent key strokes don't appear to be recognised by VA", are you referring to keystrokes that would trigger VoiceAttack commands, or to keystrokes sent by VoiceAttack intended to trigger functions in a third-party application?
From your screenshots I assumed it to be that latter, in which case if physical keystrokes don't have any effect, keystrokes sent by VoiceAttack or another application aren't going to have an effect either
That'd be something perhaps the author of the target application would need to look into