Just had time to watch this.
I don’t think any are truly resistant. Some just find a way to avoid the spores for a long time. There was an original tree in Farmington, NH that they were hand pollinating with that I believe started succumbing in recent years. There’s another one in Maine that they found when flying over the forests as well. The further north you get the more it seems the blight is less intense. There’s planted trees from the 1800s in Wisocnsin that are finally beginning to get hit by the westward spreading blight as well. There’s high elevation trees in the Appalachians that are mature and producing viable nuts so it has struggled going “upward”.
SUNY ESF is going to be distributing their Darling 54 gene edited tree soon. I’ve soured on that project in recent years. I liked what the woman was doing in the video with growing out saplings and injecting them with a dose of blight to test their resistance in a controlled environment.