Amazon is known for taking immediate action when contacted for comment from the media.
I heard this from a big-time frum Amazon seller, who has groups etc. He said that he was quoted by big media outlets a few times for grievances he had, and each time, Amazon reached out to him as soon as they were contacted for comment by the outlet. In fact, he said that his problems were always solved by the time the story ran.
In this case, Amazon can ban the seller immediately, and put measures in place to track these sellers in the future.