First up, and article from the latest issue of US Weekly where Grey's Anatomy exec producer Betsy Beers talks about the upcoming season, with a tidbit about Cristina and Owen:
Kevin McKidd is currently directing episode 9.04 of Grey's Anatomy and he tweeted yesterday that William Daniels, who played Cristina's proctor at the end of last season, is back guest starring on the show and working with Sandra Oh again:
@_haleyhenry_ it's going great ! Sandra and bill daniels are awesome today !
— Kevin McKidd (@TheRealKMcKidd) August 30, 2012
Did this just clear up the mystery of the older gent?