So here is the process
First I drilled a small hole all the way through to the shaft below. Second I drilled a larger hole in the top of the grip to give the epoxy a good place to fill, and hopefully hold.
Then I took a bit of wood and drilled a hole, epoxying the rod into it. The black tape is to protect the threads.
I pushed the wood (and the screw) up into the grip from beneath and made it ready to epoxy in place.
So there we have it. Threads I can screw my phone/camera onto, making a steady holder for the beast. I added the wing nut to protect the threads and the small string to make it harder to lose the nut when not on the top. This added .4 ounces to one of my walking sticks.