There's a hilarious meme out there, I wish I could post it, that sort of reflects this dilemma.
Q: "Sleep with me, Kathy, and I'll get Voyager home..."
JANEWAY: "No."
Q (to Kim, who's standing right behind her): "Harry? Same deal."
15 minutes later, Voyager is zooming past the Golden Gate bridge.
Regarding quick fixes by Q, in the relevant subject, there's precedent of sort in "The Autobiography of Jean Luc Picard". Before his death in Nemesis, Data was revealed to have downloaded his memories into B4, whose primitive positron brain can't properly process them. Q later shows up, declares that "I'm not doing this for you, Jean Luc, I'm doing it for him. I miss him." and Zap, B4 gets an upgrade and Data's back.
Something similar could have happened with Kes, had she been present in Q2, especially if she had been involved in the plot itself. Q or Junior might offhand remark that "yeah, I might have pushed back her morilogium by a few decades".
Even failing that, they could have (instead of doing Before and After) had the Ocampa lifespan genome be recessive. Kes passes on at nine years, but her half-human children will experience a normal life. That would be a nice bittersweet ending.