Aim Offset Producing strange rotations

I’m hoping someone here can help me. I’m trying to create an aim offset and I’m pretty close. But as you can see in this video the heads rotation is not exactly moving in the way id like in the blendspace and it looks very strange when played in game on the second half of the video. Currently all the additive poses use mesh space.

Anyone know what the issue might be? I created these poses using the third person character control rig