So your solution is for a group of miners to "solve" a potential theft by stealing bitcoins from other miners?
To avoid miners wasting effort on blocks, this could be phased in at a certain block number. There would be no need for miners who are following the consensus to surrender any earned rewards. It is just a matter of whether the majority of miners would choose to support what is just, that is all, and choosing not to have their own effort mining used to support a massive fraud or theft.