Vermicast that has completely dried out probably had some sort of loss of microbial life. The microbes live in the moisture barrier on the surface of particulates, so if there is no moisture left then the microbial life had nothing to host it. 

Most compost analysis looks at nutrient levels, density, and maturity based on free ammonia and carbon dioxide, not necessarily microbial populations. You can remoisten this casting collection and hopefully any remaining microbes can perk up a bit, otherwise, I’d suggest using it in your garden anyways as it will still add organic matter and help buffer the soil and add humus material. 

Vermicast is always best used fresh. It is not the same as thermophilic compost piles, and does not need the same curing time as conventional compost does. Use any future collections of vermicast immediately or keep in cool shaded areas for preservation. Remember, if the vermicast is bone dry, there is likely a reduced microbial population because microbes live in the layer of moisture on the surface of particles.