Office 2021 LTSC Standard 2021 Install - Error code: 0-2048(0)

Hi, at our org, we've been using the following instructions flawlessly for 2 years:

https://www.techsoup.org/support/articles-and-how-tos/how-to-download-and-install-microsoft-office-products-requested-from-techsoup

Then, all of the sudden, it has stopped working. At the point of Step 4 (in the above instructions), once the "setup /configure configuration.xml" command is run, the installation throws an error, 0-2048(0), and says something like "Could not find specified file path". Checked all the path references, etc. and all looks good.

These are brand new or newly reset laptops, so nothing is strange with the hardware. All previous versions of Office, Office 365, etc. are removed. And, again, this has worked 25+ times over the past 2 years, even as recently as August 2024. But has since stopped working.

I have checked with TechSoup (where we purchased the licenses and received their installation instructions) and they said there is nothing they can do and referred us to Microsoft. Any assistance would be appreciated!