I can't talk for Silkk and Rayzah but I think much of the people that started to get into New Japan from 2012 knew that it existed but had no real interest in finding it. What ROH did was make people go
and move from their comfort zone.
I think on one hand you had the F4WONline group that started to pay attention to it because Dave fell in love with the product. That gave New Japan some buzz, twitter fandom became more aware of it and sites like VOW started to gather more of a following. In 1-2 years that buzz became a "thing" within the IWC so NJ and their wrestlers became more well known.
Then you have the ROH fans that probably knew about the company and their stars but didn't see the point of seeking their stuff out. Once they saw them in ROH and what they could do, everything clicked for them and started to look on their own.