Hi Catfish,
you have to think of there were two Aviatik companies.
The picture displayed here shows a fighter prototype from the german
"Automobil & Aviatik AG" foundet in Mülhausen/Elsass,
that moved to Freiburg/Breisgau before the war and in 1916 to Leipzig.
In 1913 it opened a branch office in Vienna that formed in 1914 together with the "Weiser & Sohn AG" a new company -
"Österreichisch-ungarische Flugzeugfabrik Aviatik GmbH", short called
"Aviatik-Austria".
From 1916 on, when Julius Berg joined the frim, he started to design own aircraft that were often named "Aviatik-Berg X.YZ"
The site you linked offeres little mixed-up details mainly of the german developements but showing pictures of austrain machines.
(There were other firms like the "Gustav Otto Flugzeugwerke" in Munich that fromed a subsidary "AGO" in Berlin.
Both continued to design own aircraft and I often don´t know how to name them, if identified first...)
For the engine I found the
195 hp Benz Bz.IIIb (Bz.IIIbo) was a V-8 engine.
It also powered the AEG DJ.I & PE or Albatros D.X & Dr.II.
(I doubt the use of it with the Aviatik-Berg D.III as often qouted.)
Cheers
Aquilius