I took some pictures of the hinges after the test. Pinning would not have helped in this case. I used to pin hinges in the seventies, with toothpicks. Used to blow epoxy into the slots with a flattened straw. What a mess.

These hinges are designed for CA or epoxy. They have a rough exterior. I wouldn't have believed it had I not done this test. I used thick CA.

Here's the tech notes from Tower-
FEATURES: The specially textured nylon helps fast setting CA's or epoxy get a strong grip for fast lasting bonds.
It is shaped to insure bond strength at (3) critical points:
1- At the edges 2- On the surfaces 3-Through holes

Customer will not have to wait for epoxy to cure before moving to next step.
Special roughened plastic material designed to be installed w/CA or epoxy.