Texture/Shadow Issue with Jin Hair G8M

RedSoul

I'm having an issue with the specified Hair. For reference, here is the hair in question:
https://www.daz3d.com/jin-hair-for-genesis-8-and-81-males

Including examples at the link of what it's supposed to look like.

But when I did an Iray Preview, I got these black edges on the tips:

I played around with as much in the Surfaces tab as I could think of, and when I turned off the Opacity for all of its pieces, I got this instead of the hair being totally invisible:

It also seemed like the direction of these black blobs shifted when I changed the direction of the environmental light in the scene, so I'm wondering if this is an issue with how the hair model is dealing with the shadow effect?

I am on Daz 4.15; I haven't updated because of the Ghost Light issue with the latest versions (4.20+), so if there a way that this issue can be resolved, or is updating my only option?