I have a Bentley Continental booked in for the full works in 3 weekends time so unavailable to help.
What I would say though is that if its been keyed then its likely that it will need painted. Porsche paint is super hard and would need heavy compunds to try and remove heavy defects then refining stage to remove any compound buffer trails. If its not been keyed too deep then it might need wet sanding. If you have never done that before I wouldnt go sanding someone elses car. Best to get a scrap panel to experiment with first. Its taken me some years to gain the knowledge and I started with scrap panels before takling anything of value.
I have wolfs compound for removing sanding marks on hard clear coats. Its a very heavy compound and needs to be treated carefully and I always measure depths of paint prior to going in.