Qimage does not support CMYK profiles, if that's the issue.

DNG Profiles work with Adobe DNG files as well as RAW files direct from the camera, in conjunction with Adobe software such as Adobe Camera RAW (the RAW plug-in for Photoshop) and Lightroom.

From what I understand, DNG Profiles can be more sophisticated than ICCs in that they can be dual-color and allow for interpolation between two different color temperatures within one color profile based on the white-balance of the RAW data; however, they are created with a 24-patch color-checker and as such may not be as precises as ICCs. DNG Profiles can also contain hue twists to keep colors looking better across a wide range of intensities, but the ones you can create with the public profile creators, either X-Rite's or Adobe Lab's one, they don't have hue twists.

The righthand part of the info given for each photo in the View Print Queue area is the profile.  sRGB and AdobeRGB would be possibilities for JPGs coming directly out of a DSLR and is a seting in the camera, itself.

If you are making adjustments to the photos in some program like Lightroom or Photoshop, then the profile that is embedded in the photos is determined within that photo-editing program and may be different.   Can you confirm whether these JPGs are direct from the camera or have been manipulated by some other program and whether that program has been used to export or save new copies of the manipulated images?

The reason for inconsistency between WOW and YUCK can be a mis-configured profile, somewhere, or double-profiling, where both QImage and the printer are trying to account for the profile, or even the printer being set to Auto Color and trying to fix an image that QImage has already adjusted and sometimes guesses well and sometimes does not.

What file-format are the pictures you're printing: TIF, JPG, RAW, and any difference between the WOW or YUCK ones?

What is the ICC profile embedded in the original images you're trying to print: sRGB, AdobeRGB, ProPhotoRGB, and does this change from the WOW and YUCK images?