Thanks for the template file.
After an initial test, I observed the issue as you mentioned by converting your template file to PDF file format. I found that category axis labels are not showing of the chart (bottom left chart) in the output PDF, see the screenshot for your reference:
I have logged a ticket with an id “CELLSNET-45188” for your issue. We will look into it soon.
Once we have an update on it, we will let you know here.