Hm - does the actual throttle on your controller work in this configuration? If you highlight this control mapping and move the throttle back and forth, does the white bar on the screen move to show the sim recognizes the control? If it does, that’s fine, I was just surprised that it considers the separate throttle to be Joystick L.
For the rest, you can reset them to default if you like. Just be on the lookout that the defaults aren’t duplicating the controls already assigned as you noted above. Otherwise you may end up with odd controller behavior while in the sim.