The Final Arbiter's corpse shouts 'Warders, prepare, this one has failed its task!'
Source:
https://www.youtube.com/watch?v=gIrbPifttx4
Found another death shout
The Final Arbiter's corpse shouts 'This one has fallen, none are left for now.
Source:
https://www.youtube.com/watch?v=Jg5wEmUoQpg