Then you do what everyone else does; farm it out to people whose expertise is in the required area. All that we're talking about is a database with an interface that calculates certain set data, and a "look and feel" interface that matches the context of the information.
They have the database. They apparently have graphic designers and playtesters, who could dictate the information present and the look, and feel of the interface. There's not a lot left. Hell, they could have even gone to one of the developers/companies that currently do competing product, for other games, who would likely have been glad of the new revenue stream and have the needed specific knowledge.