The only things in the book that I've seen contested substantively are that the guy Kerry shot to get his silver star may have been wearing pajamas instead of a loin cloth and Rassman's claim (from the bottom of the river) that Kerry was being fired upon when he came back from him in the Bronze Star incident. I'm not aware of anything else that's even contested. For heaven's sake, Kerry's own account of the Silver Star incident conflicts with the citation.
The pajamas claim was from the VC in Ca Mau, who gave differing answers to Nightline and to the AP reporter who interviewed them a month or two earlier. The Vietnamese Communists are notorious liars (and I say this as the husband of a S. Vietnamese woman who grew up on the Delta).
As for Rassman's claim, I'll cut him slack and say that he confused friendly fire for enemy fire in the heat of battle. All the other SWIFTees say he's wrong.
I've been following this very closely and that's my take also.
But Rassman's claim is very shacky. Since he was under water at the time. Gardner had a good take on what really happened. Essentially saying that when the mine exploded we all started firing which was SOP. Then ceased after it became obvious there was no enemy fire.