Okay so here's a bit of closure to the great car seat poosplosion of 2011.......

After exploring several different (and rather expensive) options, I ended up finding an exact replacement of the seat at a local wrecker (which is great for resale down the track as our car is only just a year old!) and had it fitted at a local mechanic, all for cheaper than what my excess would have been had I claimed it. And now - THE SMELL IS GONE! Woohoo! I could sit in and smell all day, not a hint

So all sorted and I feel much better now. Thanks for all the hints and tips and advice, and thanks for asking Heather - our friend is okay now but was pretty darn sick at the time. Never seen anything like it, and believe me I never want to again. And next time I think I'll offer to pay for a cab