Dude, its Wild West gun range.
They are the biggest sham of a gun shop I have EVER been to.
I bought my handgun (Mark23) there before, it took almost 2 months to transfer it to me. Then I wasted an entire trip there because they said they had mags for it, but they were for something completely different (not even a USP)
Trust me, Wild west are ALL brainless. ESPECIALLY the management. The women (owner) argued with my friend that there was no difference at ALL between 5.56x45mm NATO and .223 rem. (ya know, 20000 PSI is no big deal right?)
I don't think anyone can blame you for being given the wrong info, but a place like P&D or even Milarm is much more knowledgeable in firearms than Wild West.