That sounds really frustrating! I’ve just measured the pattern, and there is less than a 1/10″ difference between the length of the armhole and the sleeve, so I’m not sure why you’re finding it too long. I imagine you’ve checked to be absolutely sure you’ve cut the right sizes for all the pieces, right? One additional thing you could try to ignoring the notch at the top of the sleeve and just working with the underarm notches to get started. Have you added gathering stitches to help ease it in? I’m trying to think of other possible causes for this. It’s a sleeve with a low cap, so there really isn’t any ease and it should not be larger than the armhole. You’ve used a 1/2″ seam allowance for everything?