Even on my 4,5mm ndls, I end up with a gauge of 17sts for 10cm, so I adjusted the pattern a bit to make it smaller. The 3/3LC’s are now 2/2LC’s, and the (k1,p1) is only repeated 3 times instead of 4. With only a double (not triple) pattern repeat, this brings me to a cast-on of 92 sts (44x2+4).

Before I start, I can’t seem to figure out why there’s 1 extra stitch at the beginning of all rounds. I wonder.

COWL
Cast on (94)sts. Place marker for beg of rnd. Join, being careful not to twist sts. Work in K2, p2 Rib for 7rnds.
Next Rnd: K2tog on first 2sts, on 29-30, and on 61-62sts - (89)sts at the end of this rnd.
Begin Cable Pattern
Rnds 1 and 2: K1, (p1, k1) 3 times, k4, p1, k1, p1, k24, p1, k1, p1, k4; rep from around.
Rnd 3: P1, (k1, p1) 3 times, 2/2 LC, p1, k1, p1, (2/2 RC, 2/2 LC) 3 times, p1, k1, p1, 2/2 LC; rep from around.
Rnd 4: P1, (k1, p1) 3 times, k4, p1, k1, p1, k24, p1, k1, p1, k4; rep from around.
Rnds 5 and 6: Rep Rnds 1 and 2.
Rnd 7: P1, (k1, p1) 3 times, 2/2 LC, p1, k1, p1, (2/2 LC, 2/2 RC) 3 times, p1, k1, p1, 2/2 LC; rep from around.
Rnd 8: Rep Rnd 4.
Rep Rnds 1-8 until piece measures (48.5 cm) from beg.

Next Rnd: (check how rib lines up with pattern at bottom side) Kfb, p2, k2; rep from around WHILE doing kfb twice more, lined up with the decreases on the bottom ribbed rim – 92 sts at the end of this rnd.
Work in K2, p2 Rib as established for 6rnds. Bind off on 7th.

Update:
It’s finished and it’s beautiful, but I still don’t see what the reason is for the extra stitch at the start of the rounds. Or why that stitch is not repeated throughout the rounds (which would have you end up with two more sts - in my adjusted case just one more stitch).

Update:
We’re 2015 and finally I got some pictures for this project. Still pretty. He’s been wearing it a lot and I love that he loves it. The second pic also shows the ribbed beenie that I made to go with this cowl.