By reading your post one gets the wrong impression that the Sartana name was dubbed in the german version like so many Djangos for commercial reasons.
But also wrong is that the german title was chosen for commercial reasons, because Mille dollari ... was released about 2 years before Parolini's If You Meet Sartana. So, even in germany there was no Sartana fame in 1967 to make cash with.
Contrariwise it was (according to an interview with Garko) the german title (on a film poster) which inspired the producer (not Garko as claimed above by me) to use the name Sartana again, even if it was a completely different character.
But there was always much confusion about this.