You can't know that, but if your knives work well for you, does it really matter who made the steel?
My friend's sorrow came with really thin edge at 20° (maybe even less) out of the box, after cutting into bones several time during deboning meat - the edge was still sharp and had no damage.
Do that with AUS8 at same edge geometry and you'll have instant spots that reflect light...
My guess is that RealSteel either perfected their HT or made tweaks to their D2 composition (or maybe both).
If a large company like them uses some steel for wide variety of knives - it really pays off to make some tweaks to both, HT and steel composition while keeping prices low, which is in this case what the OP is after.
Same here, lots of people swear by them here, and I just ordered one too, after handling my friend's knife and seeing how it performs while he uses it.
From sheath and performance to fit and finish - it's hard to beat them for the price.
So yeah, OP might want to give them a look...