OP, I know what I say might sound harsh, but its purpose is to give you focus.
Unless the council have regularly sent emails, let's say for the past 3 years but without prior notice did not do so this year, then it's no-one's fault but yours.
Also, adjust your perspective pl. All the CEO knew, and all the council know until you engage with them, is that a 33 year-old car with an expired resident's permit was parked in a short-supply resident's parking place for which residents, through the permit system, pay the council to enforce in order to maximise their chances of being able to park somewhere near their homes.
Of course they removed your car.
IMO, there's no responsibility or liability which attaches to them for doing so if they followed procedure.
I can't see any docs in your link - these are needed in order to examine the propriety of the PCN and removal.
As regards the other PCNs, the 14-day discounts expire progressively from 5-12 August. This means that you cannot be considered a 'persistent evader' and raises the question of why remove after the 6th PCN. This is for the authority to justify.