The Genesis design would retain the original's twin towers and turn the structure around 90 degrees.
A spokesperson for WNSL said this was impractical. He said that turning the stadium 90 degrees went against Brent council's planning brief, as the construction of an external concourse would block a road running by the stadium. He said: "I don't think it's possible. It goes against item number one on Brent's planning brief."
A spokesperson for Genesis admitted that this problem had yet to be tackled. He said: "This is one of the issues we are going to have to look at with Brent council."
Genesis originally put forward its proposal in 1994, when Nally approached Wembley plc to buy the stadium. Wembley plc refused.
There are believed to be five plans on the table: the two referred to, a second, smaller Foster and Partners design, and the proposals that the stadium should be relocated in Birmingham or Coventry.