Vim was born in Amiga and Amiga OS came with some Emacs clone.
As for where Vim was born, hardly matters, it was someone with UNIX culture background, that happened to own an Amiga.
As the sibling comment points out, MicroEmacs isn't really Emacs.
Also Emacs history is older than UNIX, and overlaps with Lisp Machines.
I think they mean MicroEmacs. Despite its name, it was not Emacs, but it had Emacs-like keyboard shortcuts, multiple buffers, and macros, which was quite neat for a free 1986 application on a home computer.