Well, I'm happy to announce that Hertz are refunding the cost of the flights in full (and also a cheeky little 10 euro admin fee they tried to sneak in) and that APH are refunding the full amount of my parking.
It took some chasing up from me but I have to say the customer service departments at both Hertz and APH were very good, if a little incommunicative.
Drinks are on me, whatcha having?
I'll have a water ... gym later ...