User blog comment:Nmrls/What are you looking forward too?/@comment-4967138-20130106063124/@comment-4928331-20130106140520

The Team (and League) learned about the existence of a new Partner only after the all-female Bialya mission, when Miss Martian did a number on Shimmer.

So Jason Todd's death is unlikely to be Reach-related; otherwise Nightwing wouldn't have spent so long a time trying to decipher who the Light's unknown partner was.