Failing to cast to BPs & can't figure out why, please help

You can enable the Draw Debug Type and set it to Persistent to have the LineTrace visualise in the world. That should give you a better idea of where it’s going and what it’s supposed to be touching.

If the LineTrace isn’t reaching your object, then you need to change its length or start/end points. If it is going through your object, but not registering it, you need to change the data in the Object Types array.