Vince there should be no bill to foot. The UKA permit now is a fixed fee based on the number of runners regardless of whether they are with club or not. Also the unattached in UKA rules refers to First Claim status rather than EA Affiliation.
So as long as the club is affiliated, which Rossy are, and the athletes are first claim members of Rossy, which it seems they are, then they should run as attached.