But Janeway could have tried an old military tactic known as subterfuge. Offer the Kazon the array if they will allow them to use the array to return home, and just leave a few explosives behind set to detonate after the array is activated.
The Kazon were already out for blood, they'd have refused any deals.
Which is why they should've just eliminated that whole "We need the Array to go home" plot point and have it be clear that any chance of going home that early died with the Caretaker.