Only reason I suggested that was because it doesn't hurt anything to add the shrimp. Depending on how the cured rock is shipped, there may be a lot of die off, or just a little. If a little, then you might not see any detectable ammonia at all, and be left wondering where you're at in the cycle. And with that little amount of die off, you most likely won't detect any nitrates. But if you throw a shrimp in there and it starts decaying, and after a couple weeks you STILL see no ammonia and your nitrates are rising, then that's pretty good proof you're good to go.
Yeah... the shrimp in a baggie with holes in it is a good thing. Wish I'd of done that the first time! Yuck.