George Roussos is credited in the Grand Comics Database with anonymously inking the Dr. Strange story "The Return of the Omnipotent Baron Mordo" in Strange Tales 114 (Nov/63). The comment suggests that he may have been brought on board because Stan Lee wanted to rush the story into that issue (Dr. Strange stories appeared in 110 and 111 but not in 112 and 113).
Actually Steve Ditko had plenty of time to ink the story. And then Stan had the time to have Roussos do artwork corrections.
Roussos inked Victoria Bentley. I might have said he redrew her, but I see Ditko's poses still there. Dr. Strange himself, Mordo, and so on, are pretty much Steve Ditko's work, pencils and inks. Roussos may have contributed a bit more—on this page, the tree in panel 3 and Mordo's hands in panel 6 look like his brushstrokes—but to my eye the men's faces are more finely inked than Victoria's.