I'd try them. The worst that will happen is they won't sprout. I've planted hige varieties that are several years old that have sprouted. I'd soak them overnight and plant them. Good luck.

Morning Glory seeds remain viable for many years if stored properly in a cool, dark, dry area. I have grown MG seeds from my 2002 plants that germinated just as easily as from my last years plants. A friend of mine successfully germinated MG seeds that were older than 40 years.
So, go for it!

Emma