Hey @RodericDarkwell!
Instead of using the “Set Relative Location”, try changing the camera boom’s Socket Offset to 0,-35,0 since for the right side it’s set as 35.
You may have to adjust the target offset as well, but it’s just as simple. 
The problem here is you’re adjusting the camera boom’s location as a whole instead of the offset. You should be able to just invert the Y offset and it go to the same spot on the other side of the character.
Just tried this to make sure it works, give it a shot. You might not be able to do this with a lerp, of course, but you seem like you can figure it out pretty easily. I think the main thing is you need to set socket offset instead of moving the entire boom.
