Hi Matthew,
That said, we are pretty limited in how we can assist you with this. The biggest issue that I can see is in
line 35 - mirador is looking for the code it needs to create the viewer from a minimized file, and is using a relative path. This means it's assuming that this code is in your AtoM directory somewhere, and all the other dependencies needed to run Mirador (for example NodeJS, grunt, etc) are also present.
If you manage to dig through the Mirador project documentation and find what you need, then I'd suggest creating a new mirador directory inside AtoM's vendor directory, and updating that path to point to the right place. Also, make sure you read through all the other dependencies (like the 2 examples I mentioned) and that these are installed on your AtoM server!
Good luck!