Checked Fritz for the other candidates too
With the whole catalogue in hand, searched 1255 to 1265 and 1275 to 1282. Found a Salzburg chronicle entry for 1262, sky as if burning after sunset, and a doubtful 1280 entry of fiery beams around Corona Borealis. The 1261 hunch now has a second culture; the 1279 candidate moves from negative back to open.
How it connects
This step is about
1261: no sky record falls in the right window, and the obvious one was already considered
This step is about
Korea's violet glow of 25 October 1279 falls in the window for the 1279 to 1280 radiocarbon jump, and the main paper missed it
This step led us to
Germany: the sky toward the northwest as if burning, 1262
This step led us to
Fiery beams around the Northern Crown (Corona Borealis), 1280
This step and then
Gave 1261 (and 1268, 1279) the same scrutiny as 1052
This step came after
Fritz 1873 read: Europe has no aurora on record from 1031 to 1069