Is there a Saskatchewan connection ?
Have you posted / researched in the USA.
Immigration Records to USA -Citizenship records - some family members may have applied for U.S. Citizenship - Records can be obtained from the State archive where application was made - or from National Archive in Washington DC
Have you searched at the Latter Day Saints Family History Centres - they would know if registrations other information has been filmed - can be very helpful.
Search Family Search org - re SCHMATZ
https://www.familysearch.org/Have you posted to message boards for the areas?
Mailing lists -subscriptions required but there is no fee.
Have you been in touch with Germans from Russia
http://www.grhs.org/-do a google search -
http://www.ahsgr.org/Villages/villages.htmHave you searched USA Census to 1930
Cheers,Stella