The dampers being used in works WRC cars aren't exactly "customer racing". Who knows they can have some technology we' may see in "customer racing" only next decade. If Citroën decides to not work with Reiger, I think it's more likely they do it because no opponent (like M-Sport) would benefit from the knowledge Reiger may gather from Citroën... Hyundai has also changed supplier, they used Reiger with the first i20 WRC, now they use EXT. As a works-team, not being able to afford it sounds rubbish to me.