if there were a bunch of those symbols (all on one single room I might add) that absolutely seems suspect

Technically, I could understand that... IF the in-game character living in that room, were supposed to be a Nazi sympathizer. Otherwise, it's a clear dog whistle.

Otherwise, rules have changed, and that symbology would no longer get the game insta-banned in Germany... as long as it was only used "in an artistic way":

Germany lifts total ban on Nazi symbols in video games (10 August 2018)