You have an amazing treasure there. I've been researching the Wends of Texas for some years. We may have an ancestor or two in common.
I can't say anything about the symbol on the trunk, but I'd really like to know what it means, too.
The oldest daughter of my Great Great Grandfather, Michael Dube, Johanna Christiana, married Michael Kurio (Kurjo) in the Serbin settlement after his first wife Magdalena Rudel died on the Ben Nevis of cholera. I have not been able to find a marriage record but suspect that they were married in the breakaway St. Peters church, the earliest records of which are still missing.
My Great Grandfather was Karl Traugott Dube, Michael's second son. I'd be very interested in exchanging information, stories, data, whatever, from anyone related to this group of Wendish pioneers.