Hi Sandy
Qimage has done me for the last 13 or 14(!) years so I'm not into dng raw.
Sorry about assuming that you had used PS. You said you had a .dng file. That is a default of saving a raw in Adobe. I knew QU didn't make that.
I am aware that raw files don't have an inherent colour space - but my Sony A77 raw declares aRGB which I suppose is the result of the processing Sony uses to create its raw files.
As you said, Raw files have no inherent color space. One has to be assigned when the image is decoded for viewing.
In the EDIT PREFERENCES RAW OPTIONS menu, you can select either colorspace for your raw images' Adobe rgb or sRGB.
You can customize your raw images.
I first had to learn about Adobe RGB when I bought a Minolta 7i which had Adobe jpegs as default. Lots of people complained about poor, washed out colours. Minolta should have had sRGB as the default but they designed for photographers and not their marketing people (who would have had a point for once).
Adobe RGB is generally accepted as a somewhat wider colorspace supposedly able to capture more shades of color, and therefore, more accurate.
sRGB is generally accepted as the standard for monitor viewing. It more closely matches the monitor color space.
Either one will be quite fine.
I did exploit a cheap offer on Elements for some of its tools but
TSK TSK or as Terry has taught me, Tut Tut!!
Fred