HILT bake incorrect

Firstly check the scale of the hilt and leather, you may need to apply the scale (CTRL+A > Scale),
Then double check your normals on the hilt and leather, just to be sure.

This will be back in Blender... you will have to re-export if there are errors in Blender.

Would you be able to share an image of the UV map for the hilt and chalice piece in Blender as well? Possibly overlaid on top of your leather strap mask, that'd really help! :)

It looks like there is an issue with the bake.
The hilt in the bake image is larger than the area of the hilt in the UV's.

I think the problem could of been caused in Chapter 3 Lesson 1 Preparing the handle. Check the scale (and normals) of the braids and hilt in the high poly collection.

So at a glance I would agree with Adrian, it appears that there was a discrepancy in the bake. The image below is a quick comparison of both the mask and the UVs you sent. It looks like the mask has basked much larger than the hilt, resulting in it not lining up and also being displayed on other pieces. If you open up the mask image in the UV editor in Blender and overlay your UVs over it, does it look something like below?

It could be possible that the scale of the object is doing this, or the wrong piece was selected and baked to. It's tough to have a solid answer at this point, but I think we are honing in on the root problem!