Retribution and the spectacular optics jut LOVE to not show up on the reward list.
Took me 5 runs to get a Retribution, and still haven't seen the optics.
Grats!
About the worse thing with Threnal is that it is just time-consuming. Don't get me wrong, I enjoy running it once at-level on each of my characters, but farming it with a capped one just starts to feel repetitive...especially east 3.