It's no bother. The center sts from the fleurette pattern are indeed
k1, yo, ssk, k1, k2tog, yo.. but that's not what you want to follow here.
You want to work the center back sts from the chart (7sts) which are part of the horseshoe pattern:
k1, yo, k1, S2KP, k1, yo, k1
So the sts between the markers are then: ssk, k1, yo, k1, S2KP, k1, yo, k1, k2tog
To me it looks like these sts are substituted for just the single center back fleurette motif. It's a shortened horseshoe in place of that one fleurette.
If you look at the next row in the instructions it's:
Dec row Work pat row 7 (i.e. the fleurette pattern) to marker, ssk, k1, yo, k3, yo, k1, k2tog. Thats not row 7 of the fleurette. That's narrowing in the horseshoe.
Try it on a swatch to see how it works and whether that's what you want to do.