Item description:

Just walk forward and watch the cutscene and the 1998 achievement will unlock

I also included a save set a few mins before the end which should be just outside the shop and i'm unsure how this game saves collectibles but if you walk past the shop then look to your right you should see an audio log and that is the last one in the DLC and it may or may not unlock that achievement too (untested) also as the game loads the latest save just delete the newest save so the game loads up the other one