There are several upgrade files for LG DVD players in the JP1 File Section and all but one of them use the NECx1 protocol with a device code of 45 (the odd one out is a VCD player model number LG FL-R888K, which uses device code 46).

I then looked up this device code in my OFA files and found that it matches the following DVD codes: 0591, 0741 and 0869. The latter two codes aren't that common, but the DVD/0591 code is present in most OFA remotes.

Now, I should mention that I didn't compare all the button codes to see if they match, but as your earlier post seemed to imply that you'd tried an OFA remote and it didn't work, I assumed that you still had the OFA remote and figured it couldn't hurt to give the code a try.