It's pretty common for things like that to happen. There are many other cases. Calculus from Newton and Leipzig being another example. There is even a wikipedia page delving into the concept: https://en.wikipedia.org/wiki/Multiple_discovery
Basic hypothesis is that once enough precondition for an invention are there then the leap can be made.
I stared for a long time at your third sentence before I remembered that Leibniz is the correct name of the German mathematician you are referring to, and Leipzig is a German city (where, coincidentally, he was born).
Basic hypothesis is that once enough precondition for an invention are there then the leap can be made.