The first three I read like "__ dimensions that are zero", the last one useless/borderline gibberish - it sounds like "isn't that just an int, not an array of ints?"
So yeah, my description above is a bit off, I guess it's the articles that do it? Is "some" considered an article?
A two-dimensional (int[x][y] not int[]...[2]...[]) "array of" int isn't really a array of ints either - it's a array of arrays of int. So a zero-dimensional "array of" int is a int.
I'd call the last one ambiguous: it's either a group of (dimensions that are zero), or a (group of dimensions) that is [of group size] zero, and the text doesn't provide enough information to know which without context, just like "I read books." when you don't whether someone's talking about their hobbies or what they did over the summer.
"Dimensions" plural agrees with "zero" as a count, so that reads as "the count of dimensions is zero".
But they used singular "dimension" with "the" which treats "zero" as an adjective. It means "the dimension that is zero".