I know this is an old post but I had the same issue and ended up finding a resolution, since this was one of the places I looked for an answer and didn’t find one I thought I would share what I found here in case it helps anyone else.
From Get Input Settings, you’ll need to enter the Action Name of whatever the Action Mapping is called you are wanting to get the keybind(s) from, it will output the mappings into an array, so the first mapping should be the first in the array, you’ll break that to get the key display name.
Hope this helps.