The "list" of resistance priests has always been spurious. It has been known to include, at any given time, any priest who is or was nominally critical of the SSPX's flirtations with Bergoglio. E.g., Frs. Morel, Abrahamowicz, Gruner (RIP), and Kramer. An actual contribution to some organizational entity (be it Fr. Pfeiffer's group, Bp. Williamson's, whomever) never seemed to be a serious requirement to get on the list. It's just a bunch of statistic padding to give former SSPX-attendees the "comfort" they lost when they vacated the social confines of the SSPX. Make it feel more like a proper "group" with a name and members and all that.