Appearance of Screen Effect on Object Changes On Export

I have a black object set to a screen transparency effect, like so:

It's all on a layer underneath the object it's supposed to outline, like this:

When I export it as a PDF, I have it set to "No Color Conversion". However, when I export the PDF, it suddenly looks like this:

It's suddenly at a much lower opacity.

Any tips? Would really appreciate the help.