Aside from what's already been said, I would consider taking your fuel system (bit of effort I know) out and giving it a f*cking good clean with injector cleaner and than some, so pump / hoses / tank / etc. This would stop further Unleaded getting where it shouldn't. That is what I'd do, bit different but have been in your boat before.
As for insurance that was mentioned above, the contaminated fuel rule of thumb will only cover (in 99% of claims) if the correct fuel did not meet the Australian Fuel Chemical standards, not for this "Oh sh*t I've used the green pump instead of the black one!". They will also take samples, exactly the same as you'd send to Cavpower or Volvo to do testing for your service's etc. That's from my other half who's a Team Leader for Suncorp Insurance Claims. It's extremely common she reckons.