Ok, it's at his base. Is that the right location?
Yes it is.
This being said, what the fuck happened in the second screenshot of your first message ?
The figure parameters say that the figure is X Rotated by -60° and Z Rotated by 70°. But it's clearly not the orientation shown in the viewport ; assuming that you haven't moved the camera, it should be Y Rotated by 90°.
Here's what a X Rotate -60 / Z Rotate 70 mean :
And there's no need for the figure in my example to be on her knees to see that it's clearly not the orientation shown in your screenshot.
Same for the third screenshot, where the figure is clearly Z Rotated by -90°, but the figure's Z Rotate value is at 0.
I get that the Hip bone have been rotated, but I don't understand the logic behind the values, especially in the second screenshot. It looks like the guy who made the pose randomly rotated sometimes the bone, sometimes the figure, until he reached the orientation he wanted.
If it's the case, then it would explain the problem you're having.
Daz Studio isn't always good at understanding that the actual pose have both the figure's parameters and the bones' parameters changed. Depending of what is stored in the pose file, it sometime decide to totally forget about one of the two (figure's parameters or bones' ones) and consider those values as if they represent the default pose.
Therefore, it add the pose on top of the actual, instead of replacing it ; keeping the effect of the values, but resetting the values themselves. What can lead to such aberration like your third screenshot, where there's no possible doubt that the figure is rotated, but the value express no rotations.
To know if it's that, just answer this question: Did you have problem when you apply a pose on a figure in the default pose (first screenshot), or did it only happen when you try to apply a second pose to the figure ?
If it's the second case, then my guess is probably correct. Just ensure to reset the pose of the figure before loading a new pose, and you should be good.