I know quite a bit about the Jostmeyer family. I can tell you this.....The correct spelling if they came from Holland would be Jostmeijer. The dutch alphabet does not have a "Y" in it. Most likely from the Volgas camps and is German and with some Netherlands root. I believe that it is a combination of two names that they chose to use when Johannes defected here to escape the war in Europe. Its a mix of Josh/Jost - Myer/Meyer depending on there location. I have found that John Myer came from Amsterdam Holland due to the fact that that was where the Norwegian ship line came to America. He was 19 and running from his father who wanted him to join in the war. He chose to be a farmer instead and had many difficulties with any profit. He was a heavy drinker and resorted to fits of violence often. He was born in 1874 and arrived in America in 1893 porting in Illinois where it had been prearranged for his to have a job and housing through a minister friend her in the states. I believe Johns brother William arrived shortly around the same time give or take a couple of years. Every document has a different spelling so I will list them.
Its been a journey to trace them, but i understand and i was able to tell my mother where she comes from.
Good luck and best regards,
Josephs descendant :)