Very specific filter feature, need help!!

If it were not for the inclusion of “newsfeed” in your criteria, I’d say it is possible, even if I don’t quite follow what you want to do. But a feed is a feed for all comers. Any filtering would be up to the feed client, not the feed provider. So I’m inclined to answer “no”.

Now, you could create specialized feeds, like the one available for comments. But they would be for general criteria decided upon in advance. It’s impractical to dynamically create a feed based on one of any random author’s profile attribute.