Pathfinder Divide adding extra paths

I'm trying to create a white plate for print, and I'm having this issue where the divide tool has added a new path crossing over the existing art. Here is what it looks like, before and after:

You can see how the line cuts through the end of the "100%" and "Vegan". I've tried a few things, but I can't figure out how to fix it. Using the direct selection tool to fill each shape, or clicking into each layer to fill it doesn't work, it just fills the entire black area to white.

Another weird thing is that the PDF save file does not show this, instead, it looks exactly as it should. But when I open up the PDF in Illustrator, bam - the line is there again.

Any ideas?