This is honestly, the worst.
Did like, Anakin never tell his son after death "Hey by the way, when I was an evil irredeemable monster, my Master had a contingency plan I knew about that could threaten the entire galaxy if it fell into the wrong hands. I know he's dead now and definitely isn't coming back, but you should probably take care of that too. Death stars were just a distraction I guess, but when you live your life a slave to bureaucracy you don't question stupid or redundant administrative decisions."
I was fine (I'm lying) if the Final Order was kept secret by all but Palpatine and those assigned to thr project... but the fact that Vader knew now makes it impossible to suspend disbelief. HE KNOWS, becomes a force ghost, and doesn't divulge every dirty secret of the empire for Luke to take care of? I mean, even with the perspective of "He needs to find his own way," I think a fleet of literal planets killers would be the one exception considering at the time he was only aware of the two Death Stars the rebellion blew up already.
It's complete nonsense. They shouldn't have tried to touch this with a 49 and a half foot pole, especially in a Vader comic, who inevitably redeems himself.
Dumb dumb dumb.