Duotone split channels

Hello - I hope that someone can help me. I am having problems with photoshop not splitting my channels when I select duotone. All of the questions on the forum that I have found refers to how it is done. I know how it is done. I am able to go through all of the steps and it says it has been done but when I look at the files they are exactly the same file on each of the split channels. I am prepping a bunch of images and suddenly the program just stopped doing what it is suppose to do. I have restarted my computer and I am at a loss. So here's the deal, I have a color image as a raw file, I put it into a PSD, I render it B&W in Adjustments > B&W and then I turn it into a greyscale image. After it is in a greyscale I turn it into a duotone. I choose my tones, light orange dark blue and the I choose multichannel. Then in the channels flyout menu I choose split channel. It does it but both channels look exactly the same. Any ideas what is going wrong? I have PS 2015.5.1 and I am working on a Macbook Pro. Thank you for any help you can offer.