Depending on how old they are technologically, the warhead has a CEP (Circular Error Probability) of about half a mile. Meaning, it will hit within half a mile of where it is aimed. Explosive warheads are probably in the 2000 pound range meaning it will destroy the building it hits and damage to progressively lesser degrees surrounding buildings.
Two thoughts. He can’t move the missiles into his chosen redoubt so he is using them up so they can’t be used against him when he and the remaining Alawite supporters move to the area around the Russian occupied port. (The rebels are allowing convoys heading to this area to go unmolested to avoid a protracted fight for the capital. But they surely would stop obvious weapons that could be used against them from a distance. Also, the regime has been conducting ethnic cleansing in the region of the redoubt and on the projected new border.) Secondly, the scuds are only a terror weapon with no significant military value. I suspect that the rebels won’t be impressed as they’ve been about as terrorized as they’re likely to be and it will simply spur them to fight harder. But it will probably reduce their numbers for future conflicts with the Assad regime in its new home.
Another thought. The US official didn’t give his name because he was discussing classified information. Are there no US officials with honor and integrity left?
Military members are always warned never to talk to reporters. They have to be refered to the base Public Affairs office. The reason being reporters love to interview anyone they can find wearing a uniform and claim its an "official" source.
Reporters will call recruiting offices or bases to do telephone interviews. These interviews then become unnamed sources.