He made no estimate of that and didn't mention SES-9. What are you reading? Is that in the original audio recording because it's not in the article.
His criticism was that "it requires flying additional fuel to perform the landing", which I interpreted to be about weight and not fuel cost, and that ULA's plan is to parachute the rockets down, I assume to minimize that problem. Do you have information that contradicts him?
Where is this coming from? [Deleted last sentence]
What matters is how much you can put into orbit. RTLS hits you with a 30% payload penalty, a normal barge landing is about a 15% penalty, and a crazy hail-Mary attempt like SES-9 is somewhat less.
If your payload is under that threshold then the only downside to it is the extra cost of fuel and support. Both are completely minimal. For example, SpaceX's next ISS supply mission has plenty of margin for an RTLS landing. A Dragon stuffed full of cargo still weighs less than what Falcon 9 can put into the ISS's orbit and land back at the launch site afterwards. For a little bit of extra fuel, you can potentially save a rocket stage worth tens of millions. That doesn't sound dump to me.
For those few payloads that can't tolerate that penalty, they can fly the rocket expendable. It's still one of the cheapest out there even if they don't recover it. Or they can fly it on Falcon Heavy, which if recovered is cheaper than an expandable Falcon 9.
The only big unknown right now is the cost of refurbishing a recovered first stage so it can be ready for another launch. That's what made the Space Shuttle cost so much more than it was supposed to. It sounds good so far, but until they're doing this on a regular basis we can't know for sure.
Really, the fuel thing sticks out at me. Maybe I'm making too big of a deal about it, but reuse is going to be very important, ULA is working on their own version of it (recovering just the engines, not the entire first stage), and he ought to know about it. Or if he doesn't, because details are for underlings, he ought to know what he doesn't know about it.