I guess 'not proven' is the same as 'aus Mangel an Beweisen ' - basically, not guilty 'for not enough evidence' (I am not an expert on this). This was a thing, I believe, but they don't use it any more.
I like the idea of a jury, it feels less authoritarian and more democratic, in practice beside advantages it can have disadvantages, I guess (like impressionable juries).
Germany does have the rule that once you get a 'not guilty' verdict, you can't be tried again. There is a case of a guy who got a non guilty verdict on a murder, later was proven to be the murderer via DNA but then could not be prosecuted. (I got aware of that only recently, always thought this was a US (and UK?) thing).
So, I sure hope the case against CB will be water tight.