If anyone else is having this issue with the grappling hook randomly failing:

–Clicking and holding will register as a click and release sometimes.

I think I found a solution. Go into Options>Controls and disable Mouse Smoothing.

Mouse Smoothing is only related to X and Y controls, not clicking, so I don’t know why this fixes it but it does.

My mouse isn’t failing, I tested it here: https://www.onlinemictest.com/mouse-test