Hello! I am sorry you had to go through this. I managed to do a CalyxOS on an FP5 from a Windows computer, part of the research I had to do came from this forum post, so I appreciate your indirect help. I put my findings here: Troubleshooting Installing CalyxOS in FP5 from Windows
In the hopes I can help you and everyone that sees this, since this link is highly ranked in google search for these issues.
Thank you everyone for making this community grow by being a part of it! I am very happy to be a part of it