Weak Answer to The Big Question
"If some newly discovered factor can account for the climate change then why aren't carbon dioxide and the other greenhouse gases producing the warming that basic physics tells us they should be?"
So most scientists are careful not to state human influence as an absolute certainty. Nonetheless, the evidence is now extremely strong.
In other words the models show it must be human GHG so if it isn't then the models are wrong and that is inconceivable.