My timeline applies rotation to my Player (not Player Rig, but the Player Child of it).
See pictured my code from my PlayerControls script:
My timeline plays, with all rotation working as expected, then when it ends, the Quaternion.Euler rotation is applied:
An example of the rotation that I have applied using my timeline is on the 1.5 second mark, a rotation of 22.5 is applied to the z axis, resulting in the following: