Between a K and a P you would normally bring your yarn forward between the needles, but not YO.
In this instance bring the yarn forward, over the right hand needle, and back to the front to do the purl stitch. You'll end up making an extra stitch on the right needle just as if you did a YO between two knit stitches.
If you look at the portion of your pattern between the **, you sart out with 6 stitches between * *, and with the 2 'new' stitches the YOs create and purling 3 together (2 stitch decrease), you still end up with 6 stitches in one repeat of the pattern. If you DON'T have six after doing the * * then something's wonky.
I hope so!