They didn't outfight the Odyssey, they destroyed in in a Kamikaze attack. Those tend to be pretty effective when you're a flying antimatter bomb.
"Scorpion" is where everyone keeps saying the Borg Decay started, because the mere THOUGHT of there being ONE Species out there that could fight the Borg was utter heresy to them because for some bizarre reason they saw the Borg as some ultimate enemy.
They're not, they never were. They're just cyborgs who are tougher than the Feds.