Huh, I'm surprised that's not in there. Can confirm; that's the only part of 30 I've been on (went to the lakes to the west several years ago).
Out of the 3 routes that end at the old US route west of I-29 (the others being 15 and the eastern 20 segment) this is the only one that's wrong.
Since it's in Brookings County, the new endpoint should be CR 77, as Brookings does a pretty good job pentagoning important county roads.