personally, i think the bounds skewing is fine if the observation is legitimate. the observation here wasn’t hidden exactly. (it wasn’t obscured nor private.) it just didn’t show up on the map for whatever reason. i’ve seen cases like that before, and it’s possible that it’s just been fixed. see https://forum.inaturalist.org/t/map-does-not-show-all-points-for-a-species/2305.
that said, this particular observation seems to have had its photo flagged and removed. so it’s now a casual observation and should no longer skew the map.
if you’re building your map thing based on the iNat Range Map thing you referenced in your original post, then i think your “from” clause would need to reference a single center point (or a bounding box that you would determine the center point for) and a zoom level. i’m not sure why you would need multiple locations.
if you’re intending to filter the observations by location, then that’s another thing, but then that would probably require that you have a lot more of your own code to support that kind of filter. (that’s the way i would have built it, but i don’t think it’s a quick thing to do if you haven’t already done it.)