QSK.
No, I don't recall that the Unicom fellow is an accredited Met observer, but, nor does he need to be as there is a fully staffed Met office on the airfield at NLK.
When I operated there on a regular and reasonably recent basis, the information provided by Unicom when the weather turned to crap was of a very high standard and of great use in making decisions. In these circumstances it was not uncommon for NLK to deploy observers onto each threshold to give immediate and accurate appraisals of the actual weather to support that info being given via Unicom from the Met office which, incidentally, has a radar facility to to facilitate their information. I would be extremely surprised if it was any different last Wednesday evening.
In the case of NLK, Unicom is manned for every arrival so, whilst your suggestions as to a safety initiative are appropriate, they nevertheless occur anyway on NLK irrespective of any legislative requirement etc.