In paragraph 805 of the final version of the Goldstone Report, he does not find corroboration for any specific incident he details but he finds something he considers relevant:
In one incident highly relevant to the cases investigated by the Mission because of factual similarities, a soldier recounted an event he witnessed.(448) A family is ordered to leave their house. For reasons that remain unclear, probably a misunderstanding, the mother and two children turn left instead of right after having walked between 100 and 200 metres from their house. They thereby cross a “red line” established by the Israeli unit (of whose existence the mother and children could have no knowledge). An Israeli marksman on the roof of the house they had just left opens fire on the woman and her two children, killing them. As the soldier speaking at the Rabin Academy’s “Fighters’ Talk” a month later observes, “from our perspective, he [the marksman] did his job according to the orders he was given”.Footnote 448 notes " Testimony of 'Ram' in the Rabin Academy Fighters’ Talk, pp. 6-7. The Mission notes that “Ram” clearly states that he was an eyewitness to the incident."
So, although Goldstone did not find any direct corroboration for the terrible stories he tells of heartless IDF soldiers consistently picking out and shooting women and children from close range, he felt that "Ram"'s supposed testimony to the Rabin Academy acts as a reasonable proof of the Palestinian Arab testimony.
The problem is that after Ha'aretz published the Rabin Academy talks, the other Israeli newspapers went to great lengths to find out whether the stories told were true. This specific incident was especially heinous and one of the soldiers that recounted the incident was tracked down by Israel's Channel Two, and he told the reporter that he did not witness the incident and in fact was not even in Gaza!
In addition, the IDF investigated the alleged incidents mentioned. From the Jerusalem Post:
From Ma'ariv (translated by CAMERA):"All of the soldiers who were involved in the conference were questioned - not as a punishment - but in order to understand whether they had witnessed these things. From all of the testimonies we collected, we can safely conclude that the soldiers who made the claims did not witness the events they describe," the source said.
"All of it was based on rumors. In the incident of the alleged shooting of the mother and her children, what really happened was that a marksman fired a warning shot to let them know that they were entering a no-entry zone. The shot was not even fired in their general direction," the source said.
"The marksman's commander ran up the stairs of a Palestinian home, got up on the roof, and asked the marksman why he shot at the civilians. The marksman said he did not fire on the civilians. But the soldiers on the first floor of that house heard the commander's question being shouted. And from that point, the rumor began to spread," the source added.
"We can say with absolute certainty that the marksman did not fire on the woman and her children. Later, the company commander spoke with the marksman and his commander. We know with certainty that this incident never took place," he said.
Two central incidents that came up in the testimony, which Danny Zamir, the head of the Rabin pre-military academy presented to Chief of Staff Gaby Ashkenazi, focus on one infantry brigade. The brigade’s commander today will present to Brigadier General Eyal Eisenberg, commander of the Gaza division, the findings of his personal investigation about the matter which he undertook in the last few days, and after approval, he will present his findings to the head of the Southern Command, Major General Yoav Gallant.The New York Times also followed up and mentioned that the investigation found this incident to be "an urban myth."
Regarding the incident in which it was claimed that a sniper fired at a Palestinian woman and her two daughters, the brigade commander’s investigation cites the sniper: “I saw the woman and her daughters and I shot warning shots. The section commander came up to the roof and shouted at me, 'Why did you shoot at them?’ I explained that I did not shoot at them, but I fired warning shots.”
Officers from the brigade surmise that fighters that stayed in the bottom floor of the Palestinian house thought that he hit them, and from here the rumor that a sniper killed a mother and her two daughters spread.
Even if Goldstone believes the unsourced "testimony" of "Ram" above the IDF investigation, he should have mentioned that there is a dispute about Ram's "eyewitness" testimony. He could hardly have been unaware of the firestorm that erupted in Israel as a result of the Ha'aretz article. His failure to do so, when the followup information was so widely disseminated, is significant and troubling.
In short, Goldstone uses an apparent Israeli urban myth to corroborate separate Palestinian Arab narratives of different incidents - which means he has no corroboration at all.
It is hard to escape the conclusion that Goldstone wanted to believe the Palestinian Arab stories of being shot so badly (he states multiple times that they are "credible and reliable witnesses") that he purposefully cherry picked very dubious Israeli "testimony" to back it up, rather than look at the facts impartially - or even to mention in passing that the IDF claims to have discredited "Ram." Since he accuses the IDF a fortiori of not being able to credibly investigate its own soldiers, he doesn't even mention any questions about "Ram."
It is also interesting that none of the 53 anonymous interviews in "Breaking the Silence" mentioned any first-hand knowledge of wanton killing of civilians. They mentioned that the rules of engagement could end up with soldiers making decisions that would weight Gaza civilian lives less than the lives of the soldiers themselves - something Goldstone highlights - but as far as I can tell, every interaction of the soldiers and civilians mentioned there does not come anywhere close to the horrors narrated by the Palestinian Arabs. This absence of corroboration from Israeli soldiers who were upset at the Gaza operation is noteworthy - if they had seen anything like what Goldstone reports, they would have mentioned it.