You should feed Hadrurus by the general guideline of feeding it nothing bigger than about half its mesosoma. The species as a whole is known for being hard to raise up, though you have a real head-start at 2". Apparently, one thing that really helps is providing them with lots of humidity in the lower regions of the substrate. Never kept them myself, though, so others could probably comment more.
If you got a two inch Hadrurus, you got something that many people in the trade, who deal with this genus, would love to have! It isn't often one comes by them at such a small size. Hadrurus are quite capable scorpions, but being as this one is still quite small, I'd go with medium sized crickets and no more. Given, they can kill something as large as themselves, but they're more likely to do it for self defense than for food. Then, you have "food" to discard because they will not eat it.