Hard doesn't mean "durable" Hard means brittle. Like glass. It's hard, but it can break easily. It has much less "give" to it. That means that it can shatter worse with small impacts. Impregnating the slab with resin is done sometimes on stone like this in order to help it "bind" together better, but that has to be done before fabrication. After fabrication, the chips can be repaired with resin, but you're not getting resin down in to the pores under pressure.

Are the edge profiles the same on the 2 jobs? On easily chipped stone an edge detail with a moderately large radius (like 3/8" or more) is needed. A flat edge with only a slight bevel at the top or an edge like Ogee with the sharp edge on top will get shipped easily.

if the edge profile is the problem you have reason to be unhappy with your fabricator. As your stone resource it is their job to advise you of such considerations.