Ok, I tried just now, and unfortunately dont work at all. You said GenericNPC Animation, see what happens if retarget to Anim_Throw_2. I found the best way to test animations is placing on anim_BP (for example on idle animation) because in the animation sequencer all looks perfect, but with anim_BP the IK is calculating, and it brokes everthing.
Another thing I see in this video of metahumans, its the fact that is not perfect. If you see the idle animation, look the legs how are more straight.
And, If you have the Pedestrian animation pack, one animation called Kneel_START.
It seems that after the retarget the feet are pulled hard to the ground, bending the legs and not letting the feet “slide” on the ground, like this kneeling animation.