By the conclusion of the Molotov-Ribbentrop Pact were German Balts, if they wanted to leave the former Latvian citizenship, resettled from the entire Baltic States to the so-called "Warta Country" inside Poland.
Since Johann Eduard Iwaninok’s mother's maiden name was Lipke, it may be that Edward Iwaninok and a possible relative of Marta Lipke (German Balts name), there is the possibility of relocation.
Subsequent entries I have found in the former offcial Latvian settlers list from 1940:
17106. Iva?inoks, J?nis, dzim. 1903. g. 9. janv. R?ga, dz?v. R?g?, Auces iela 10, 6. dz., 14. XI. 261. 1939. g. 21. XI.
Translation: #17106. Iva?inok, J?nis (Johann), born: 9th of January 1903 in R?ga, residence (1939): R?g?, Auces iela (street) 10, flat #6 Motion for dismissal of the Latvian citizenship: 14th of November 1939 Dismissal of the Latvian citizenship: #261, 21th of November 1939
25153. Lipke, K?rlis, dzim. 1882. g. 20. janv. Lietuv?, Kau?as gub., dz?v. R?g?, Stabu iel? 92, 6. dz 11. XI. 258. 1939. g. 15. XI.
Translation: #25153. Lipke, K?rlis (Karl), born:20th January. 1882 in Lithuania, Kaunas/Kowno gouvernement, residence (1939): R?g?, Stabu iel? street) 92, flat #11 Motion for dismissal of the Latvian citizenship: 11th ofNovember 1939 Dismissal of the Latvian citizenship: #261, 15th ofNovember 1939
These entires, if relevant to the requested persons, are a good basic for further research of former ancestors, for example inside the Latvian online church records "Raduraksti".
To use Raduraksti, a cost-free registration is required.