Only just joined myself (ie 1pm 24/06/21) so don't want to tread on any experts feet, especially as I will be looking for help myself later.
However have you tried any of the treatments for the plastic headlights, you tube abounds with how to on them but I don't know whats best.
I did get some reasonable results with my sisters Scenics headlights once using houseold CIF paste (I heard toothpaste works) and fine wet and dry plus water, as ever I would test a small area first
and I would hope the trade stuff would work better, although they still look like paste and polishing paper.
You will have to watch the proximity of teh spoiler though.
Hope it helps
Kel