Well if it's across the top of the dash and it can't be fixed, then the only option is a dash out job. Not what you want to be doing. But I've seen stuff online before, trim repair experts, for example years ago people used to drill the dashboard to fit clunky handsfree kits and I've seen those drill holes repaired... So what you're looking for really is someone in your area who specializes in trim / plastic / upholstery repair / retrimming.