No, I believe they are stating that the chassis was designed by a Red Bull company called Red Bull Technologies (which is not involved in the Concord Agreement), and not by Red Bull Racing (which has signed the Concord Agreement). So technically STR isn’t buying the chassis off RBR, but from Red Bull Technologies.
And I believe Super Aguri are doing a similar thing as the car is being designed by a third party, but I don’t know if they’re creating a new chassis, using the RA06, or using the RA07.