Small part of OG mesh won't go away!

1). We only need to see the blend file you imported in s4s. We can tell what you cloned by the info in the warehouse;
2). You should watch more tutorials on the subject, preferably the ones where the author actually explains why, not only how.

Some items are split into multiple parts to tune each of them differently. The item you cloned is split to hide necklaces and armbands. Each separate part of it has an entry in Region map, which dictates what it will interact with and in what way. You do not need to touch Region map, all you need to do is split your mesh the same way the original you cloned is split