This is a "bad apple" picker, not a bad design for an apple picker. Its designed to pick rotten apples off the trees. The deer, ground hogs, fox, possum and racoon clean them up pretty quickly and the tree can devote resources to the healthy apples.
Acetone-ABS slurry weld the two parts and find a long piece of bamboo that is about 1.5 cm at the end. You can drill a hole in the side and put in a pin but a pressure fit works just fine.
The "connector" file is for connecting two pieces of bamboo for a longer reach.