That is really impressive pattern uncovering XD As for whether or not to remove items, I'd say it is your call! Mistakes definitely happen in data entry. I did something similar with the guide, someone reported an additional super-rare item in a sector that had a confirmed one, after putting together the tables it became pretty clear that it didn't fit with the pattern.

If there are actually 2 independent reports of the item, I'd be more hesitant, but at the very least we can flag it and remove it if it never shows up again.