Dear Jamie McGuire writing about abusive characters and romanticizing abuse is actually a regressive trope which reflects the 70s and 80s elements of the alphahole hero. That is not pioneering the NA genre. The faster this element can die a quick death the better.
Authors shouldn't claim to pioneer a genre. Most especially if the said genre they belong already existed and pioneered by others such as authors like Liz Berry and Judy Blume who pushed the envelope and broke new ground. And actually created controversies decades before. They could also write rings around this author and dared to tackle dark issues with a good grasp of characterization and intelligence.
You did not create or write anything but was lucky enough to ride the popularity train of a genre that was already in motion partially due to the rise of self publishing and P2P platform. It was St Martins Press who was savvy enough to see this rise in the genre that predates your books being published a few years before and called it New Adult as a good marketing and classification ploy. So I think they helped to pioneer the genre.
True pioneers of a genre is Jane Austen, Mary Shelley, HG Wells, Charles De Lint, Stephen King, Anne Rice, Kathleen E Woodiwiss. I can go on and on but these authors helped to shape specific genres into what it is today.
Note: And considering you marketed and pushed your series as YA is pretty disengenous because when the genre and audience emerged you changed your tune and revised your own history. That is not a mark of a pioneer.