If you did, indeed, read the Owner's Manual, then I congratulate you since far too few people bother to do so. However, there is a bit of an art to getting a response that you want when posting a question. If you have read the manual, it is a good idea to state something along the lines of, "I checked my Owner's Manual, but it is silent on this matter".
Yes, I assumed that you did not read the manual, but since a huge percentage of the questions on this board result from not reading the manual and since you did not tell us that you had read the manual, it is not a quantum leap for someone on this board to assume that you didn't read it.
As to the issue of whether the transmission is built in Japan or not, this may relate to what I mentioned previously--that many "automotive journalists" do not have sufficient knowledge of what they are being paid to write about. For that matter, I read the other day that your car is built in Belgium. If that was true, then it is unlikely that engines and transmissions would be shipped from the US to Belgium in order to be installed in a car that is then shipped to the US. Thus, whoever wrote that the car is made in Belgium is probably also wrong.
Those issues aside, have you determined if the transmission is working as it should?