There were no communicated filetype requirements for the first assignment. Since I know MS office works with open doc formats, I wasn’t worried. He didn’t tell me to send MS office formats. Instead, he told me to use MS office. I wasn’t going to pay (even discounted) for a product that has (for me) been 100% replaced with libreoffice. So, I tried just sending him the files in MS office formats, which worked to appease his requirement. He later did send an email to the class, asking that we only use MS office and avoid foss office programs. I realized it was him misunderstanding how these software work, so I didn’t really sweat it. I’m assuming there was some incompatibility with their cheat-check saas that caused this requirement.
There were some embedded objects in nearly all of the docs, but no equations.