I purchased 10 - Lavlin yeast packages several months ago. I forgot about them and left in the envelope in my room. It says to refrigerate . Has 2017 expiration date. I'm in desperate need to use one and don't have anymore.
I would follow the "rehydration" instructions on the package and make a starter by adding a little sugar. In about thirty minutes you should be able to see it "working" if it's still good.
I would put money on it that they are just fine, these yeast packets sit for months in kits unrefridgerated, Like jpike01 said, make a small starter just to make sure. put the rest in the fridge.
