Interesting how they talk about ED2 for once, as it's always about Calty it seems. The SC430 of 2001 was one of the first models presented as a production design proposal for final approval, when ED2 opened in 1998. Much of Sotiris Kovos' design for that was reached in 1997, during the last years of first generation SC. That was first shown in October 1999 as the Sports Coupe Concept. I don't believe it couldn't been designed fully at ED2, considering when ED2 opened in 1998.
The 120-Series Land Cruiser Prado was designed here back in 1999 (GX470 was in 2000 in Japan), as well as the 3GS (S190) in 2001-2002, the first production L-finesse design. L-finesse was inaugurated back in 2001 as the 3GS design process and development of the 4LS began. 2IS development was well underway by then, reaching styling approval in 2003. The 2IS was designed at Lexus Design Japan studios in Aichi.
The current IS reached final design approval well over 4 years ago, as I remember a Lexus executive referring to it being "reached" already back in August 2010 and called "radical". Probably wasn't 100% "final" yet, but likely critical decision making was already happening at ED2 for the design (as hinted at in the article).