إلا إذا كانت علة الحكم منحصرة في معنى
Unless the cause of the ruling is confined to one particular factor.
This exception is decisive. If reliable evidence establishes that a specified legal consequence has one exclusive sufficient cause and no alternative cause applies, absence of that factor can support absence of the consequence.
But “this cause is missing here” and “this is the only possible cause” are different propositions. The former identifies a missing factor; the latter requires proof of exclusivity. Without that second premise the negative conclusion does not follow.