Certain filled in fields in a PDF form only visible in preview pane or when exported to jpg/png

We have a PDF form that was made, with numerous fields. About 20% of those fields, when filled in, are not showing up when viewed in Acrobat, Reader, or a browser. However, if you use the Windows preview pane, or preview the document in Outlook if it was emailed, OR export it to an image, the fields show up. We are on Windows 7, and all of this was filled in, and created, by Adobe Acrobat DC.

On the left is the file open in Acrobat, and on the right is the file within the Preview Pane of Windows. I've redacted sensitive information but you can clearly see the fields are populated whereas on the left they are not.