You seriously think that Rossi wanted to follow Stoner to try to copy his lines?
What is clear is that stoner made an insulting gesture, and that rossi interpreted this as stoner saying he was seeking or in need of a tow.
I have not seen any direct statement from stoner that he thought rossi was seeking a tow, and seeing the gesture was made in australian and interpreted in italian the correctness of rossi's interpretation may be in some doubt, although not the intention to insult.
I think it is fairly irrelevant anyway, as has been said (I think by rossiofsky) stoner was looking for any excuse.