There isn't a "correct" way to incorrectly render the interrobang as 2 separate characters. The name was never supposed to suggest a certain ordering instead of just being both at the same time. The name "interrobang" just sounded better than "exclamaquest" (or any of the alternatives Type Talks readers submitted).

No, it should be rendered with the proper Unicode: U+203D ‽

do you really think so?!

I think bang-interro just didn't sound as nice and that's probably why it is called an interrobang.