Hi Pat, There sure are a lot of different ways to spell Emil.
It's hard to say for sure if Emil was Ferdinand. In the Detroit Directory 1879 it listed both Emil and Ferdinand living at 112 Mother. My GGrandfather and other Dornbrocks lived on the same street The name was later changer to Cleveland St.
A descendent of Albertina Gust went to Trinity Lutheran Cemetery last summer and he said there were 2 Emil Gusts buried there. He also had sent me a letter from the Detroit Public Library stating that Henriette's full name was Henriette Florentene Gust
In the 1900 Census it listed Ameil (Emil) Gust and wife Gertie. In 1910 his wife was Katherine. These old records aren't very reliable. The Gust families passenger list said they all came from Switzerland in 1873
On Anc.coms trees I found Frederick John Gust son of Wm and Henriette Gust born on Dec. 28, 1838. Emil was supposed to be born Jan 14 183? Emil Jr. was the in formant on the death certifcate. Maybe he didn't know his grandparents names. Things like that happened a lot.
My greatgrandfather on my mother's side was born in Germany, France and Switzerland according to different records
Johanna Gust married Herman Schulz son of Constance and Ferdinand Schulz.
I think I found her in the LDS website, born 1811 in Poland. She married someone else there.