Here's a thought:
I was struck by the fact that the first witness's name was Gottlieb, same as the father's "surname." This, and knowing that deaths were often reported by family members, I was suspicious of the similarity of the surnames Mann vs. Pfann. I looked up this original death document on Ancestry.com, and confirmed that there was a transcription error, that the witness's name was actually Gottlieb Pfann.
I suspect that the witness was either an older brother or cousin of Moises, named after the grandfather, giving further credence to the theory that Gottlieb is a patronymic.
Hope this helps!
Pittsford, New York, USA