Yep. But I think it's easy to show that this is circular, since you can't know BB(754) without knowing whether it runs forever.
And you can't prove that it'll run forever without seeing it go past BB(754) and still keep going
BB(754) is X if ZFC is consistent, Y otherwise
Since you can't prove that ZFC is consistent (only disprove), you can't know BB(754), which is the thing we were trying to use to determine whether ZFC is consistent in the first place!
The definition doesn't make it obvious, but this is just the same as plain Gödel incompleteness, we can't get any extra info about ZFC even in principle (unless we happen to see it halt, by chance)
But if you run it for BB(754) many steps, you will know.