The first n I dated was a very typical overt narcissist - outgoing, grandiose etc. My last ex was a very quiet, introverted 'nice guy' (covert) who had over twenty years experience in working with the upper management end of difficult customer complaints - he turned out to be an absolute master at witholding, projecting, intimidating, stonewalling and gaslighting. I blamed myself for everything so it took me a long time to figure out there was abuse and I only put the finer details together, in the end, with the help of the amazing staff at a womens' refuge I needed to stay at when it was all over. They were the ones who clarified all the nuts and bolts of abuse (decreasing the survivors options). I didn't know anything about NPD and hadn't realised my first ex was a narcissist until after this last relationship.
I don't know anything about 90 day Fiance but it sounds interesting. The show I was talking about is a reality series called 'Married at First Sight'. Its really awful how the relationship 'experts' are joining in on the gaslighting - even telling a victim not to trust her gut at all in one session. From what I understand, it is quite common for narcissistic perpetrators to fly under the radar with therapists, authorities, judges etc and this can really pile on the victim blaming.