How to undo bind off stitches in the middle of a row

I’m knitting a dog sweater and at a point in the pattern for the leg openings where I had to knit 13, bind off the next 10 stitches, then knit 82, bind off the next 10 stitches, and knit the last 13 stitches (total 128 stitches on needle). At the end I’m supposed to have 13 stitches on either end of the bound off opening, with 82 in the middle.

Well, I’ve never bound off in the middle of a row before so I miscounted everything and have the wrong number of stitches on either end of the bound off openings. I don’t want to just rip out, I’m going to to back stitch by stitch and undo everything (tink) but I don’t know how to undo the bound off stitches when I come to them, to put them back on the needle.

Everything I’ve searched for undoing bind offs are for undoing them at the end of the project, not in the middle of a row. How do I do this without messing everything up even further?

Just lift the bound off stitch back up to the R needle.

But the bound off stitch is ‘flat’ on top, where do I put my needle?

Undoing in the middle of a project isn’t really different from undoing the final bind off. Just insert the left needle into the stitch below the bind off and pull the yarn to undo the actual bind off. Do this one stitch at a time and you should be fine.
This video is a little dark but it should show you the idea