squishys is correct. The two lowest scores are the ones that involve fine motor. Although expectations are admittedly low in kindergarten, I would still keep an eye on this, and possibly seek additional evaluation by an occupational therapist, as the Coding score is two SD below the next lowest score (Block Design), which is, in turn, a relative weakness within the Performance Index (1 and 1+ SD below the other subtests in its cluster). The remaining subtests are all clustered fairly closely (depending on where in the 99th %ile Matrix Reasoning and Vocabulary fall).
Late developing fine motor may or may not be purely developmental.
These are also the two timed tasks, so a highly conscientious or perfectionistic task approach, or anything else that interferes with speed, might also lower the score. Though you note IRL fine motor delays, so that seems like the more likely explanation.
