Chap I worked with out there, was informed that you were allowed to wear the ISAF minature on your Mess Dress. So, whilst on R&R in Sep last, he popped into the cheap military tailor's to have said minature added to his current crop - £50+, thank you very much. 2 days after getting them back, and a day or so before a "Do", he was told that he had been misinformed. £50+ later..........
Late summer 06, there was a letter doing the rounds from J1 either at Kabul or KAF, I forget which exactly but am fairly sure it was the former (I will see if I can find it) which stated that you could wear it on your No 5s but not No 1s as it was a non-Article 5. Not the best logic for being allowed to wear a medal, but there you have it.
However, if you look on the intranet at work and do some digging in the JSPs (someone from admin should be able to tell you which exactly) it states that your medals on your No 5s must be idential to those worn on your No 1s. And to wear medals which have not been approved by HM is a grave dis-service to HM.
Letters or verbal authorisation from theatre J1 means absolutely nothing until you see it promulgated in a DIN that you can wear it. Personally, I don't think she will care a hoot either way whether one individual puts up a NATO gong for AF, but there it is in a rough nutshell.