When did you download both the NSFW patch/beyond the bet and the base game? I suggest deleting what you have and reinstalling everything in case you have some mismatch of versions somehow, then starting a new save from the beginning of Beyond the Bet, playing through the first NSFW scene, and then seeing if the second comes up. I've double checked just now in a new run, and I can see that the scene you're after is reachable, so I'm guessing it's an issue with the files.