You should be able to just enable/disable collision on the object via nodes.
Try to drag off from the bat variable and type collision, see what you get.
Re the notify. Is the animation 1 animation or 2/3 animations combined?
From what you are saying it seems like you are triggering the “put away” at the end of the swing, but there is more animation playing until the weapon is put away so you just need to move the notify further down the animation- or to the other animation in case you are using multiple animations for .
Re the animation speed, check that the speed rate is 1 and hasn’t been changed within the animation.
The framerates doesnt really seem to matter in unreal. Generally 30fps gives you a 1:1 frame.count between FBX and Ue4. 60fps does not. At least in blender.