Kathryn was legally obligated to let the Ocampa suck it.
Kathryn was legally obligated to let the Kazon loot and plunder Ocampa and Caretakers Array.
The Kazon conquered Ocampa a generation earlier, the Ocmapa. even in hiding, were slaves who couldn't look after themselves, and Caretaker was a transient serial rapist with no claims to local space who's property became free salvage to the first way farer who planted a flag on that array, after he had died.
These were strictly internal matters Sraefleet had no business interfering with, because it dramatically altered the balance of power in the Quadrant, and it is Starfleets modus operandi not to be responsible for bullshit that's going to snowball, I mean bullshitball.
From the Pilot.
JANEWAY: Stand by.
CARETAKER: The self-destruct programme has been damaged. Now this installation will not be destroyed. But it must be. The Kazon must not be allowed to gain control of it. They will annihilate the Ocampa.
(The Caretaker shrinks into a hand-sized rock. Janeway picks it up.) TUVOK: Shall I activate the programme to get us back?
JANEWAY: And what happens to the Ocampa after we're gone?
TUVOK: Captain, any action we take to protect the Ocampa would affect the balance of power in this system. The Prime Directive would seem to apply.
JANEWAY: Would it? We never asked to be involved, Tuvok, but we are. We are.
Caretaker could have blown up the array at any point over the last 1000 years but he was a pussy. He didn't want to blow his home up, till after he died because the old bastard thought it might hurt. Wussy, pussy wussy. He relied on an alarm clock to do the job post mortem. Think of all the times an alarm clock fucked you over and you were late for work or school. He was an idiot. If Caretaker had just accepted suicide as a good call, the Ocampa would have been fine till their food, water and power ran out and they starved to death.
caretaker didn't have to be on the array when it blew up.
he can fly through space (when he's healthy) or he could have gone and to begin dying on Ocampa weeks earlier after blowing up the array, and not shortened his life span a lick, even if his natural environment is a tangent dimension he could just slide into at will.
Caretaker was vain.
He loved his home too much to see it destroyed.
Tuvok knew how to send them home, but it would take a couple hours. Hours they didn't have because, there might have been thousands more Kazon ships on their way... But there wasn't. Kathryn's paranoia inflated the potency of the villain at hand because she assumed that she was dealing with Romulans, not Pakled.
Tuvok said that it was a Prime Directive concern, and Janewy said "fuck it"
The Pilot is black and white.
Janeway is a Villain.