salling,
Are you casting on stitches in row 5 to replace the ones your bound off in row 4? That's the thought that comes to mind when I read this post.

I am guessing that you should either do a Yarn Over (YO)in the buttonhole row after you knit 2 together, or more likely cast on or make 2 stitches in the following row just above the 2 cast off stitches. You have to do something to replace the two stitches you cast off.

What you two have said makes a lot of sense. I saw other patterns that explained it like that. Thank you very much for your help!