I asked this question on one of my Lemmy alts (still playing around if I prefer lemmy or kbin) and what I was told is the stats you are seeing when you view an external instance are the subscribers from YOUR instance. So you are viewing a lemmy.world magazine/community through kbin, the 92 is kbin subscribers for that community. To get the real number you need to view the stats on the original instance (the 1000 you saw).

I think its a pretty big flaw with the fediverse software right now and I think should be a priority fix (if it is at all possible to do that). Makes magazines/communities look inactive when you are searching for them on your instance if they are external. It drives people away from subscribing (I know it did me when I didn’t understand it at first) when you do a search on your instance as you just think there is no activity and don’t even bother clicking it. I imagine it would get pretty extreme if you host your own private lemmy or kbin and when searching for things to subscribe to on your instance, everything looks empty.