I think it is worth trying a conversation with them very much along the lines of what you have put in your posts. BUT if they don't agree to extend the award which your husband got at the tribunal it is essential that you start a new application.
If you can't face thinking it through from the start again, just copy what you submitted last time, but add to the evidence a copy of the tribunal decision and say that nothing has changed / or state what has changed.
So frustrated on your behalf! Catherine
Nothing on this board constitutes legal advice - always consult a professional about specific problems