@dpotesta50 (snarky: I did amend my original post to reduce the snark level).
The unattend.xml and setupcomplete.cmd files are something created by your previous admin to tweak your windows 10 build post image deployment with company/site specific settings. You may want to review these files to understand why he felt the need to do this. I can tell you its common practice to use the unattend.xml and setupcomplete.cmd files. So the short answer is yes you may need them.
If you don’t have them, and your previous admin used them, I can tell you how to collect them (assuming they are in your master image today). Take a computer and deploy your standard image to it, when FOG is done, power off the computer. Take the hard drive out and add it as a second drive temporarily in another computer. This will give you access to the media to collect these files.