[helene_t]

I thought "bidding police" referred to the teacher or something. If the question was if there is any reason to call the director, then no. This pair probably don't have the agreement that 2♦ is nonforcing and even if they do it is not a major infraction not to alert it. A pair that plays 2♦ as nonforcing probably isn't aware how unusual it is and therefore there is no way that they could know that it is alertable.

Of course, lack of knowledge of the alert policy is not a valid excuse for not alerting correctly. But you can't teach people to alert deviations from standard bidding before they have some kind of notion about what standard bidding is.