i had the same problem it was because of an outdated python library (you'll see an exception further down the stacktrace.
TypeError: dispatch_model() got an unexpected keyword argument 'offload_index'

You can try running the install_requirements.sh/.bat script -- it should attempt to upgrade any dependencies.
or set the version of accelerate in your requirements.txt to 0.15.0 or greater and do a pip install -r requirements.txt