If the CEO thinks that a Crossrail station at LCY can be added at low cost he's in la-la land. That planning and construction opportunity sailed years ago. It would have been very easy (and relatively low cost) to add a station during construction, but the airport wasn't willing to pay for it. For context, the new stations at Canary Wharf and Woolwich have been financed by the relevant property developers - indeed Canary Wharf actually built their Crossrail station as well as paying for it.
It would be far more difficult / disruptive / expensive to add a new sub surface station once the rail service is operating - and tfl have zero interest in having anyone disrupt their new train set which is (in transport planning terms) almost ready to open.