More confusion on legislative immunity

I wrote a few weeks ago about a Ninth Circuit case allowing a state legislator to pursue a First Amendment retaliation claim against legislative leaders who restricted his access to the capitol, wondering how this was not governed by legislative immunity. Further confusing matters, the Sixth Circuit holds that legislative immunity bars a First Amendment retaliation claim against the heads of a party caucus for expelling a member from the caucus (and denying her party resources). Unless there is a meaningful distinction in the legislative nature of "you no longer get to hang out with us in the legislative process" and "you must notify us before enter the chamber," both decisions cannot be correct.