Complete the game as Ghost, then activate the "Unlimited health" and "Unlimited ammunition" codes. Play the chase levels where many Agent Smiths are chasing you. Get to the point where you get the grenade launcher. Use the grenade launcher to take out the Agent Smiths. Continue until the final part just before the last sequence in the Matrix before you get on the platform and kill the Agent duplicates. Look directly ahead at the top of the balcony. You can see Niobe walking into the mini pillars. If you kill her, you will die even with the "Unlimited health" code. Fire the grenade launcher at her, and she should climb up the fencing and walk off the building completely.