It's unfortunate that the transactions seem legitimately came from early days mining based from the timestamps' gaps.
But one Bitcoin client (node) can't just command all of the client to replace their blockchain with his own version of the blockchain.
I ask a stupid question..... if I put together 130 virtual machines (not a problem for me) , send coinbase transactions created with these private keys and have them authorized by the 130 machines, do you think it is feasible?
That will essentially create your own fork of Bitcoin since you'll build your own network of nodes that aren't connected to Bitcoin nodes.
Its blockchain will build over from the last block that your brother mined, it wont affect the Bitcoin Blockchain.