How to fix rig issues with UE4 skeleton?

I’ve been having issues with rigging a character to use in UE4. I’ve been using auto-rig pro in blender, and following the creator’s tutorial to rig my mesh with the UE4 mannequin skeleton. That said, when I import my mesh and check out the anim starter pack animations, my mesh has issues, specifically with the left wrist looking like this during rifle aiming animations:

I can’t figure out how to fix it. Adjusting retargeting options doesn’t seem to help.

Initially, I was using a mixamo fuse created character with mixamo animations, but all of their rifle animations have similar (but much worse) wrist issues inherently whenever I upload a fuse character.