EDIT :::: The Bones Fit Him OK and the Rig seems to fit … I suppose the Only way is to Put his arms closer together with Rig in Blender before Exporting Him but I thought that would not be so good for animating … ?
… was also wondering where I could uploas Grants Ogre It wasnt under the Resources under the Video… ? Thought they might want to Fight !!!
i … My orks Wrists dont fit inside the Mixamo Box … I cant see any waY TO SCALE Him ?
But he still Dances quite well with Twisted Forearms 
The armature, you’ve installed, need to match the Orc mesh.
You do that in edit mode by scaling, moving and rotating the individual bones.
Before you are going to tweak, you need to reset (delete weightpaint) the automatic assigned weights.
Show a picture what is happening …
He is an Orc perhaps his wrists just work like that! The huge advantage of fantasy creations!
That reminded me of something XD
Unfortunately it doesent look good the way it is … but the Animations without wrist movement seem to be working nicely … I added screenshots above
The Bones Matched I think … I added Images above … 
Unfortunately doesent look good the way they Twist , but mnaybe that can be corrected afterwards with weight painting ? 
Show the wrong (unexpected) wrist location…
Quite probably.
There was Bending in the middle of the Forearm which was the onl place to stick the Wrist circle on Mixamo … Ive weight oainted them now and looking better 
