So you're saying that no where on paper has the mortgage company stated that they must be noted as an interested party? If not, have they added this condition by giving you notice of the requirement?
I don't know of any insurer reluctant to add a noted party. It's beneficial for them to have this information. All broker software includes this question as standard which is then printed on the documents. Even Norwich Union (as was) has this as part of their policy and they're next to useless although, admittedly, their home insurance product isn't the worst out there.
Has any other person within the industry had this problem? Huckster. Can you advise here?