Bifrost Foam Disappearing in Refraction?

[EToth]

We are attempting to define our BiFrost-to-VRay pipeline. We have baked out the BiFrost mesh as an alembic and the foam is live rendered via the BiFrost Shader through VRay 3.4.

As you can see when the mesh is on the foam beneath the surface disappears, however, the propeller is still visible. It's as if the mesh is working as a matte object for the foam?

Any ideas?

Mesh On:


Mesh Off:


Ocean Shader Material Settings:

[yolov]

Will it help if you increase the refraction max depth (this will increase render times too).