She backed off the pressure. As she "went for" the highest part of the song, I inwardly cringed as I played the keyboard, expecting her to do what I see far too many singers doing... applying force to reach that note. And she didn't. And it came out with an unexpected clarity and openness.
Backing off air pressure is a master vocal technique. Fear can make it almost impossible without the confidence that it will indeed work. My suggestion for you:
Get out your hardest song. At the place you have the most trouble, try applying so little air pressure that it seems you're breathing the note in instead of out. Spin it, weightlessly, using pelvic floor support and having your head in line with your tailbone.
Let me know how it works for you. And look for Skye Dyer songs and concerts on the horizon. She's great.