I was able to fix this eventually. There might have been an update from Intuit, as I hadn't seen this view before, but... I went back to the income section, clicked through the remaining pages (most of which I had already done), then found myself in an income review section where the "problematic" 1099-B rows came up. I still had some challenges with some of the items, but was eventually able to get them to all disappear.
The weird thing was that some of the imports had been correct and complete from the beginning, and it was still e.g. asking for date acquired when that was already present. Anyway, taxes filed. Aww yeah! Good luck to all of you still struggling with this!
