I don't know who is in charge of the Fiesta used by Oreca now but for next season Oreca shall switch to Fabias using cars from 2C (as far as I read somewhere). Since Oreca has been working closely with Škoda since 2008 it sounds very logical. Recently Oreca is responsible for building and maintenance of all customer Fabia R5 engines. 2C on the other hand has been also working closely with Michelin providing cars for their tyre testing. Unfortunately I don't know any more details about the actual relationship of Oreca and 2C.