Toph. sussed it mate, the washer pipe does run through the headlining on the passenger side,if you pull the facia panel off between the parcel shelf and the roof linning, you can see the pipe, there is a connector there and it blows apart, probably, cause his pipe was frozen by the windscreen wiper, so the pressure built up and blew apart by here. could be something to watch out for in the future.
cheers
Cocka