Lumber man, not much more than a newbie here, my friend, and experimenting with a sawn in set back handle, so this might just be a good example of what not to do.
Okay so explaining what I'm gonna try to do with the obvious extreme grain violations and the fact that the original example is broken across the handle:
First, in laying out the handle, I tried to maintain a 1 in 12 grain angle where all pieces taper to nothing, playing with S curves to do that.
Second, using the original's belly keel to pad out thickness at the bend and distribute the load over a larger area of the belly.
Third, trying to keep the cross sections as thick as possible through the bends, and keeping the glue surfaces as large as I can.
Fourth, tapering and rounding as much as possible, with the above in mind to keep stresses spread out.
Fifth, I'm hoping to band the handle sections, transition, as well as the limbs (which the original had). I will be using hemp fiber, though, which I have on hand. I don't have any rawhide, and besides I think it will stick better as a fiber than just a strip of rawhide. Just a guess on that. I'm hoping that if the bands are placed right, they will contribute to preventing the handle pop-off that may have happened to the original, and prevent splitting. Sinew would probably work as well, but I don't have that either. My guess is hemp fibers will work, though.
sixth, I might (not sure yet) run a strip of fiber up the back part of the handle knuckle, under the bands. Not sure on that one, yet. Have to feel how it looks -- if that makes any sense.....