hyperlinks in a pages document produce tag issues in pdf accessibility test

Apple's PDF export solution is not a full PDF implementation, and does not support tags, or any features of the PDF/A-1, PDF/A-2, or PDF/X standards. You will need to post process the PDF by adding hyperlinks, and tagging information to the intended text from within Acrobat itself.

We have never recommended Pages for commercial print solutions.

Because Apple's PDF framework that is used for PDF export is so aged, compared to what Adobe can maintain in its current Acrobat and other products, it is almost a certainty that no PDF/UA (universal accessibility) standard compliance is inherent within exported Pages PDF documents.

I suggest you find someone in the university faculty or support staff that has current Adobe Acrobat Pro experience, and can help you edit/add what you need into that PDF document for the appropriate accessibility standard you need to meet. I am no authority on Adobe Acrobat Pro DC, and am unaware of a convenient PDF to help you.

Here is a link from Adobe on creating and verifying PDF accessibility in Acrobat Pro.