re: He said it right
I've always "heard" the ghost of the "a" in there. Maybe it's only because the sentence would make sense that way and my brain's filling in the gap, but it also seems to me that the cadence of Armstrong's words contains a slight gap there where he might have weakly voiced the "a". He was exerting himself physically and under stress, and that might've messed up his breath control at that moment.
That's what I think the digital analysis brought out.
That's one small checkbox for history buffs, one giant improvement in the legend.