Question is, are those attacks low profiling ALL (or at least most) Mids? If so, maybe they're intended, like how Sub in MKX went under all mids except gigantic ones with slide. And I think D4 and/or B4 might be the same way.
Well, looking only at animations it shouldn't hit even at that 2nd attempt. But considering the fact that they are closest as they can probably get it's a major flaw... Badly designed, not tested properly etc.
But maybe... it is supposed to work this way. Who knows! It's NRS.