You are missing the flatten operation from this line of code 7, which is applied using the functional API.
This code should work:
# feature extraction layer 
base_model_list = list(model.children())[:-2]
# same layers as loaded resnet 
layers= base_model_list + list(model.children())[-2:-1] + [nn.Flatten()] + list(model.children())[-1:]
new_model = nn.Sequential(*layers)

Generally nn.Sequential is used for very simple models, so wrapping all child modules inside this container might not always work out of the box.