To clarify; by what I mean 'with tweaks', is that I'm following it exactly with the exception of, I want to use my own character (already rigged) for the animations and model instead of Ellen. To that end, I have my character model already imported with rigged bones, and for animations I'm using Mixamo animations set up with my own custom Animation Controller mirroring the tutorial Ellens as close as I can. Despite this, she's still stuck in a T Pose no matter what I do; I can't walk or move, only rotate. However I know the model works as I was using it with another framework in a previous project with different animation methodologies.
Admittedly I'm very new to Animation, so I'm willing to break it down step by step with everything I'm done to get to the bottom of this. Thanks everyone!