Corrupt file after using request.get() in Python

I am trying to use request.get() to download files from the assist.org website for a research project. Specifically, when you go to the website they have a box for articulation agreements. While it would be awesome to come up with a way to go through all the drop down menus (Academic Year, Institution, Agreements with Other Institutions) and then view the agreement for each combination of these and download them, I need help for an even simpler step.

Clicking through and finding a link, the reports in the articulation agreements are stored in the URL format https://assist.org/transfer/report/XXXXXXX, where the X's are digits. Here is an example.

Clicking the link in my browser (Safari) opens the PDF and I can click the download button. But using the following sample Python code, it gives me only a corrupt .pdf file. I am not that well acquainted with HTML and websites etc., so I am not quite sure how to adjust the code to get the PDF file from the above link.

import requests

def download_file(file_number):
    url = f"https://assist.org/transfer/report/{file_number}"
    response = requests.get(url)
    
    if response.status_code == 200:
        with open(f"report_{file_number}.pdf", "wb") as file:
            file.write(response.content)
        print(f"File 'report_{file_number}.pdf' downloaded successfully!")
    else:
        print(f"Failed to download the file. HTTP status code: {response.status_code}")

file_number = "26917146"
download_file(file_number)

I tried the above piece of code, and all I got is a file that nominally has the extension .pdf, but it fails to open in Preview on MacOS.

I have also looked in the source code for the website but cannot find any references to a .pdf file...

Furthermore, contacting the people behind the webpage doesn't help much, as they cannot readily send all the PDF files yet (they are doing some restructuring).