David regarding the mud flaps, I’ve not seen a Tiguan with them fitted.
Our own car even with the 20” wheels doesn’t cause mud, stone chips to get on the paintwork due to the plastic wheel arch protectors.
Do you want to fit then for looks only?
Maybe a good place to start is look at Golf mud flaps and if it’s possible to adapt them. But OEM accessories especially from VW cost a ridiculous amount, I’d probably search Ebay and see if there is anything suitable.