In this search for 6 people https://phabricator.wikimedia.org/feed/query/J4lbsYTIjiAH/ it is also including activity from other non-listed-users who merely gave tokens. E.g. Ricordisamoa awarded T94648: [...] a Doubloon token. I'm not sure if that's intended, or a bug.
I believe the technical reason for this is that T94548 was authored by one of the users included in the filter, so they're a "token receiver" for the story, which ends up translating into the story appearing in the feed. However, I agree that this behavior is surprising and think we should change it.
Token stories have a few other quirks and are using some older infrastructure.