Honestly, I’m finding your discussion more interesting than the book. I know its reputation, but it doesn’t grab me. My problem. That being said, your explanations help. Some thoughts:
The descriptions in the book make it sound like Gold has cranked out dozens, if not hundreds, of forgeries that are good enough quality that even experts and scholars can be deceived. Considering the time it talks to do that much research (pre-Internet), master that many author’s voices, the time it took to put words to paper using an old-fashioned typewriter – not to mention the difficulties of having the books printed and bound in the 1950s – he has to be a fantastic being of some sort. There’s a difference between supernormal and superhuman.
You keep referring to the daughter as a minor. She probably wasn’t. In a lot of states, even today, the age of consent is 16. So, it’s icky and gross, but probably not illegal. Also, back in the 1950s, if a young woman chose to go to a man’s room and freely offer to have sex, it would have been on her. Our modern conception of consent did not exist.
Unclear if saying Gold looked German was a compliment or not. It might have been, in the sense that is was supposed to be better than looking Jewish, but there was a lot of anti-German prejudice at the time. I had a girlfriend back in the 70s whose family had changed their last name from Wunderlich to Wonderly for this reason.
That the mother thought in terms of Jewish nationalism is very period appropriate. Israel had not been in existence for very long. (Side note, the movie The Chosen from 1981 has a section that does a pretty good job of showing how divisive Zionism was in the Jewish community.)
Re the lack of African American representation: The story was set in a time when the country was approximately 90% white. Outside of the South and a few major cities, African-Americans were extremely rare. It’s highly likely that Weer had never seen one in his life. (Similar point about the Chinese – there’s not a person, just an artifact. Chinese immigration was banned or severely restricted until the passage of the Immigration and Nationality Act of 1952.) Also, until very, very recently, much of the country saw racism as something that only happened in the South. So, I think this was actually accurate for the period.