The post is imagary time a fifth dimension may indeed have been asked before, but the referenced post is not it. That earlier one concerns Hawking's cup to avoid the point in the cone. This one involves the expression of the metric in Minkowsky spacetime.
I can't interact with the banner where this was marked and agreed to by someone, so I bring it up here.
I disagree; the original question doesn't say that it's asking specifically about Hawking's use of the idea. It just asks what imaginary time is.
Anyway, if the closed question really is different, it should be edited to explain why it differs from other questions (including the linked duplicate). Then it could be reopened. I would note that this kind of edit is very difficult to make without changing the apparent meaning of the question, so usually it needs to be made by the original asker.
If a question is based on a misapprehension then I think it is fair to close it as a duplicate of a question that explains the physics involved.
In this case a Q/A explaining what physicists mean by imaginary time is not strictly speaking an answer to the question Is imaginary time a fifth dimension?, but it answers the question indirectly by explaining imaginary time. That makes it a good candidate to be linked as a duplicate.
In this case flagging the duplicate worked, as I note the OP posted in a comment:
Ok, I think I'm starting to get it. Imaginary time is the result of a transformation applied to time that makes it act like a spatial dimension mathematically. Imaginary time and "real time" aren't two coordinates of a complex number, they're just two different ways of looking at the same thing?
