I was involved in one in in what is now called class G airspace where they concluded that it happened 10nm east of where it actually was, in spite of myself and the pilot of one of them saying otherwise!. All very well but that put it in Rule 21 aka class A airspace, so although they were only FIS and had 500ft vertical, there was greater impact as they implied both aircraft had infringed. Once again, no contact and I had no recourse; the conclusions were published as they said!!