Sorry could you give a link to the interview between John and Donna Hill and SY, G-Unit? It doesn't ring a bell with me.
The 11 people interviewed in Dec 2014, shortly before DCI redwood were interviewed as witnesses, not as arguidos. John Hill and Donna Hill were amongst those.
I remember writing articles on my blog about who was being interviewed, why they most likely (in my thoughts) were being interviewed, and what it told us about the OG investigation.
From memory, the media was speculating that John Hill was to be asked about (possibly amongst other things) the alleged missing ring of keys for all the OC properties in block 5.
I can't remember what I actually came up with.
If it is particularly important, I'll have a rootle around in my files to see whether I have a reliable link for John and Donna.
The simple summary is that Operation Grange was still doing a wide spread trawl, as opposed to a sharply focussed operation.