I re-read the pattern for like the 20th time. It says to ch 108 begin with Row 1, work in pt st for 28". Fasten off.
So really my only question is what does Pattern Stitch (multiple of 3 sts) mean?
Row 1 2 dc in 3rd ch from hook, *skip 2 ch, 1 sc and 2 dc in next chn rep from * across, ending with skip 2 ch, 1 sc in last ch. ch 2 turn.
Row 2 2dc in first sc, *skip 2 dc, 1 sc and 2 dc in next sc. rep from *across, with 1 sc in top of t-ch. ch 2, turn. Rep Row 2 for pat.