Weird: The first time I evaluated it, I got the buggy results. Then I copied some of the pieces and evaluated them separately. The alpha line threw a syntax error. Then I deleted my mess, and reevaluated the four-line cell. Then it worked fine. I quit the kernel and tried again. It worked fine. Maybe there's a parsing error in the original notebook. I didn't edit the first cell, but maybe it got re-parsed correctly.

It won't let me add this notebook: https://www.wolframcloud.com/obj/mroge02/Published/198902202

I suspect you’ll get the expected result shown if you evaluate in separate cells. What you are seeing, I think, is a display error but (I hope) not an error in the actual assignment.