Translated: We are holding up the peace process.
Sounds to me like they are the "lock" not the "key". And you know what you do to unwanted locks...
Bingo, you got it exactly right. Syria is the key to the peace process in the same way that Saddam was the key. They are both locks that needed to be broken.
Assad is still under the delusion that his brand of "stability" is still deemed important. Syria used to cause havoc in Lebanon and close to Israel until they get what they want and then "pacify" the region.
Message to Assad: FREEDOM NOW TRUMPS STABILITY.
Let my people go (Lebanese).