I’d like to also offer you who may stumble upon this blog for my own resolve.
I reached out to the travel agent whom I bought the exchange order from, and it’s quite simple: I need to send the physical XO back to them, pay a little admin fee, and they sent the right exchange order back to me.
I also have asked the JR office directly via email.. the response came too late after I have resolved all my problem, but it also supported my 2nd friend’s solution: it’s fine. You can still exchange them anyways.
Hope this helps!