Well, if the entity issuing the TX was colluding with a miner, they'd craft the TX and the miner would add it to their mempool without announcing it to the rest

Well, if the entity issuing the TX was colluding with a miner, they'd craft the TX and the miner would add it to their mempool without announcing it to the rest of the network. Then when and if this miner finds a block, it would include this transaction.