Cutscenes can be... very trial and error-y... It takes a lot of messing around and accepting its many idiosyncrasies.
But let me try to see if I can help you...
A moving camera will keep its orientation while its moving unless you have other things telling it to rotate. So for a pan shot, you just need to point the camera to an initial position/orientation, then tell it go start pointing at another.
set-camera-rotation, set-camera-facing, and set-camera-facing object all modify the orientation of the camera, so when you use more than one of these at a time, only the last one will actually do anything.
So the super simplest thing you could do is
set-camera-rotation
0
0
0
set-camera-rotation
0
0
45
5000
But I'd say play around with the stuff and see how it works.