iCloud Files and Examplify Software (by ExamSoft)

I am using a 2022 M2 MacBook Air and running Sonoma 14.1.2. I'm using iCloud Drive, syncing to this Mac, with desktop & documents folders in sync with iCloud. My Documents and Desktop folders are on my iCloud, not on "Macintosh HD." I used to have "Optimize Mac Storage" on, but I just turned it off for reasons I will explain below.

I'm writing my open-book final exam tomorrow (Fri., Dec. 8) using an exam software called Examplify by ExamSoft. With the software, we'll be running a Non-Secure Blocked Internet option which allows students to access all files and apps on their device while blocking access to internet. This means that I will not be able to access any file that is not on my hard drive but lives in my cloud.

I'm worried that during the exam, some of my files will have ~*for some weird reason*~ been offloaded from my hard drive and moved to my cloud, thus making it impossible to access them during the exam. I got in touch with ExamSoft whether I could use a USB-C flashdrive as a backup, and they said that only files on my device will be accessible. So, not only will the internet be blocked, but so will external drives.

Pretty sure it would be fine since my files will likely still be synced to my computer. But I just want to make sure that I don't face a catastrophe.

Any tips, experiences, or cautionary tales?