Pity. Obviously there's no point in my addressing you any further, except to refer you to the free dictionary website: You will observe that "definitely existing" is not an element of these definitions. I assert that the Pilate crucifixion story is apparently reasonable, that's all. Therefore it requires less evidence in its support than, say, the virgin birth in Bethlehem.
Dear me. Craig - that definition is not at all relevant here.
Look, what you said was this -
Yes it is plausible whether it happened or not.
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- It is plausible that Jesus was executed by Pilate, since Pilate was a murderous tyrant given to the practice of executing people. .
That highlighted statement of yours is simply wrong unless Jesus existed (it assumes Jesus existed).
If Jesus did not exist then it is most definitely NOT "plausible" that Pilate or anyone else executed him.

I'm not trying to be unkind or anything like that. I just don't want you thinking that it's OK for you start building ideas on an error like that. Because you’ll just end up completely deceiving yourself.