I thought I'll post an update. I spoke with someone from the body shop of the local BMW about it. There is no way to close the bonnet once the PPS pistons fired. They also told me that 8/10 times the bonnet bends and needs to be replaced too. It sounded like BS, but upon closer inspection I did see bumps on top, just above the emblem. Not easy to spot at first but once you see them... I couldn't open it so I can't tell what damage was below.
With that, it became an insurance matter. With how insurance works here, I'm stuck with 'at fault' claim and 650 quid out of my pocket. The insurance picket up my car and dropped off the courtesy car. I'm now waiting for the repairers to notify me what will be done to the car.
If the repair quote is high and/or they'll need a long time to fix it (thus having to provide me with a ride), the insurer may still decide to cut costs and write off a perfectly good car.
P.S.: I can't believe my car panicked and blew it self up, I wan't even near BOOTS
