I was thinking along the same lines but couldn't find any evidence of Olgin as a Russian name. I would have expected to find it here -
http://mirimen.com/fam_O/page-2.htmlif it was Russian.
The Ancestry website gives the origin as Spanish, the same as Olguin and Holguin. The US distribution map on the same site shows that it is best represented in those South-Western states with a strong Hispanic presence.