If you read the report they commissioned, there's enough sq ft. already existing in the Atwood, plus another 20k sf. coming available so they have all they need.   The TI window is less than a year to complete.  The cost of improvements is less than $7 million.   If you read the report, the "opportunity cost" is theoretical nonsense designed to make it appear that there was less difference between the two.    The cost of occupying the Atwood is $1.84 psf per their own report.