Problem Solved
Gentlemen, the problem with my grapple hydraulics was solved. Pics of it in action below. That is an 18' long pine tree and tractor did not even flinch.
As a recap, this thread started with me indicating I could not get my brand new grapple to grapple. So I started grappling with the issue and got a lot of great ideas on this forum for troubleshooting. Using your suggestions I troubleshot it to something in the dealer's installation. The dealer had connected 3rd hydraulics for the grapple to the rear SCVs by running hoses with quick disconnects from the rear to the mid multi-connector, and then from the mid multi-connector to the loader boom where they installed a smaller quick connector for the grapple. All JD parts so it looks like a factory installation. When I determined it was not a grapple problem I called JD to come pick up the tractor and fix it, since I paid them to install the system.
The problem was when they routed the hoses from the rear SCVs to the middle multi-connector, one of the hoses was too tight and it was pinched underneath the tractor where they ran it along side the metal lines. They replaced the hoses with larger diameter and slightly longer ones and voila...grapple is grappling so I no longer need to grapple with this issue. No charge to me for anything including the pickup and tractor drop off.