The definition of conspiracy is to agree in secret to do something, usually illegal. The corporate media loves to label as "conspiracy theory" things that are going on that aren't really secret, the Koch Brothers plan for world domination by the wealthy elite for example, not really a secret, this is called public policy.
In order to have a successful conspiracy you need to make it as simple as possible. This makes it unlikely that DSK is being framed, way too many civilians involved. It's not like building some fake moon rocks out plaster and chicken wire on a sound stage to film the moon landings. Of course if everybody involved starts turning up dead like the people with knowledge of the JFK assassination I'll take it back. Then there is the possibility that the CIA has a drug that simulates syphilitic dementia but I think it more likely this guy is just a pig and finally went too far in a country that doesn't know he's above the law.
The theory that DSK was taken out because he wanted to supplant the USD with a new world currency doesn't hold up to scrutiny. His "currency" would have included the USD as the major component, the BRICS countries are pushing ahead with not using the USD or even Euros at all. The IMF "currency" would have held this move off and probably stabilized the USD. (unless the big "THEY" wants a completely unstable USD)
There is talk that Saddam and now Muammar were taken out for similarly shunning the USD and we do know that the sanctions against Iran have been primarily aimed at their banks. I doubt that Bush invaded Iraq for that reason, there are too many other reasons that it was a tempting target for a mob hit from the Bush Crime Family. Libya is simply not that big of a player and it's not like the other dictators that are using the USD are being spared so any noise he was making about switching from the USD isn't likely the cause.
The truth is that the rich and powerful "conspire" all the time but the really bad stuff isn't a secret, it's issued as a Policy Statement by some fancy think tank and signed by "very serious people". Allan Greenspan and Henry Kissinger have been in that business their whole lives.