That was amazingly close, although as it happened, and on subsequent replays right afterwards, it appeared to me that Phelps touched second.
Also it seems in the SI piece, that some frames are missing in that "frame-by-frame" account (shades of the Zapruder film maybe, LOL).
In another related development, the Serbs are protesting the use of Press-On Nails by Phelps...
ADG