The only other 'Senior Officer' at that time that visited those sites, and was part of 303SU, was a SEngo SO2 as the sites were 90% manned by technicians. The remainder were admin, chefs and a medic. Knowing him as I did, a stickler for detail, I do not believe that he would have asked her to keep quiet. I visited once a month and, funny old thing, no antics. My XO also went regularly. The only other officers would have been visitors.
As to the mooning. Standard practise at all the sites. Funny the first time you see it but then...
As someone said, time does not diminish the seriousness of this allegation. She can still make this formal.