Again. And I don't recall the final part of the fight being combination effort. What I remember is everybody pretty much was done by the time Luffy arrived.
The Straw Hats all got back up after Nightmare Luffy wasn't enough to take down Moriah (when he goes crazy and activates Shadows' Asgard).
–- Update From New Post Merge ---
No, corruption on the part of goverment would require A) Knowledge, B) Approval, usually for private gain.
And PARTS of the goverment being corrupt (small parts, mind you), don't put legal responsibility on the whole thing, dammit. And guilt by association is a fallacy.
Let's see.. many actions of the World Government throughout the series have been corrupt (cover ups, assassinations, allowing Slavery "in the shadows" even though they abolished it). None of these things are okay, so no, the government is not corrupt in only small ways.
And here we have the government afraid that Doflamingo will unleash some secret to the world, so they shut him up by allowing him to join the ranks of the Shichibukai and do whatever he wants. It's obviously something bad about the Celestial Dragons/World Government that they want to keep hidden, or else they wouldn't be so scared about it. So tell me, how is it not corrupt of them to empower someone in order to protect their secrets (these are the bad guys).