Yeah, it’s about that part. The thing is I have never encountered this construction before.
It’s obvious if you see both the Japanese sentence and the translation. But, if you didn’t have it how could you tell that it means shouldn’t have. It seems If you translate it literally you’d get something like: … coming to this kind of place wasn’t. I was wondering about the ん here as well, and I think you’re right, because nothing else would make sense. However I don’t remember If I ever saw the nominalizing の being abbreviated.
With this thread I was hoping someone would point me to the relevant grammar pattern either on BunPro if it’s present and I missed it somehow. And perhaps to propose this grammar point for BunPro to add sometime.
@milopiccolo great link, thanks