Wrapping all modules in an nn.Sequential container might work for a simple model definition.
In your case the inception model is failing, since inception.children() will return the child modules in the order they were initialized. model[15] would thus contain the InceptionAux module (which is used in this side branch 4 of the model) and will thus apply a linear layer to your activations.
The next layer will fail because of the shape mismatch.
If you want to change the model execution I would recommend to write a custom model by deriving from the inception model and by changing the forward definition.