No. It looks the same from the outside. Will the difference in the inert concrete head vs nuclear warhead create slight differences in flight dynamics? Yes. Will it create some sort of difference that could be measured with any technology anyone on earth has? Extremely unlikely, especially since local weather, per missile build tolerances, per sensor tolerance, etc etc would all have a much bigger impact.

So I would go with a very simple no. No you cannot tell what's in it.