Troubleshooting Formula Issues in Data Fields

has anyone had a formula refuse to run? I have a formula looking at 2 fields and it's supposed to grab the field with a value -- but it stays blank instead. I've tried a bunch of formulas, including:

I've looked at the preview pane for AI and it says it should be populating because there is a field with a value -- but the preview is not what is showing up in actuality.