So I had cleared 3 of the 5 nodes, left BP and Hawkeye. I rostered a Hawkeye just now and cleared his fight, and Galactus did not unlock. Instead, it allows me to fight the BP node, which, as we all know, doesn’t work. Fix!
Also had an unopened Galactus node after a sidenode fight with connection issues when completing.
Restarting the app helped.