Remember that he consulted with Yoda and the little frog gave him the shittiest advice possible. Even if Yoda didn't knew the details telling a a seriously troubled looking person, who got premonitory dreams before involving death that he "must rejoice" about people dying and turning into the Force (like the Jedi where some kind of space vampires, consuming the dead souls as their "turn/rejoice" into the Force) wasn't useful at all.
And Yoda was their grandmaster, The Jedi. The sage which everbody turned for advice. Also Palpatine was a friend of Anakin for more than a decade by them.
But it was really just that >>9061 Vader crushed her neck and the alien doctors where too dumb, too unschooled into human anatomy to know that.