Keep Options pushing two paragraphs to next page

In a book I'm typesetting, I have most paragraph styles set to keep the first two and last two lines together to avoid widows and orphans. But I've got at least once instance where it's pushing the last two lines of a paragraph that precedes a block quote to the next page unnecessarily, as though the paragraph and block quote were inseparable. (In screen shot below, see paragraph that breaks across pages 12 and 13, with the block quote adter.)

I've never encountered this issue and simply cannot figure out why it's doing this. I've tried turning off Keep Options on one or both paragraphs, removing the border from the block quote, turing off the snap-to-baseline setting. There is definitely a paragraph break between the body paragraph and block quote, so it's not an issue of a forced line break or similar.

The only way to get all of the lines of that body paragraph to stay on page 12 and the BQ to start at the top of page 13 is to replace the paragraph break with a frame or page break, but as this is just a design sample and could create issues later if any text changes, that's not a great solve.

Anyone ever encountered this or have any ideas? Thanks!