Passenger lists for those leaving the US do not exist. If they travelled 1st class, sometimes their names were listed in a newspaper for the departure port as traveling on a certain ship on a certain date.
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Here are 3 Possibilities for Dimiduk family, two coming to US and one leaving from Harrisburg PA
1907-possible 17 year old
1909-possible-34 year old
1912 possible, depart from Harrisburg
Hope these help
Dear Mr. Shinkaruk,
Thank you for posting your request on History Hub!
As the previous posters mentioned, the United States did not keep passenger lists for outgoing vessels to Russia. We suggest that you contact the Federal'naia arkhivnaia sluzhba Rossii (Rosarkhiv) [Federal Archival Service of Russia], ul. Il'inka 12, 103132 Moscow, Russia for the information you seek.
You may wish to use a commercial research service such as BLITZ to track down relevant passenger manifests. We also suggest that you review the FamilySearch research wiki on Russia Emigration and Immigration.
We hope this is helpful. Best of luck with your research!