I was the referenced person the OP noted in this thread. I just got my CR-1 approved in Feb. (Bangkok). I got the same email as the OP and it was the first time anything was mentioned about the petitioner having to submit original or court certified copies of marriage certificates. I never saw this requirement in any of the instructions anywhere. I did not have the time (I was in Thailand at the time) to try to locate my old marriage docs so I pretty much ignored this one-off request. I did of course supply original or certified copies of my divorce. It did not become an issue and was never requested again. I think that it is a poorly crafted email and is not an official requirement per se.