Well, all that is said there is that no one of the immediate family intervued by the Jerusalem Post told the swedish photographer about any organ theft. Not that they rule it out:

Family: We didn't tell foreign media organs were stolen | Middle East | Jerusalem Post

The mother denied that she had told any foreign journalist that her son's organs had been stolen.

However, she said that now she does not rule out the possibility that Israel was harvesting organs of Palestinians.

One of them confirmed that the rumor was and is circulating and supported the need for an inquiry:

Family: We didn't tell foreign media organs were stolen | Middle East | Jerusalem Post

Jalal and other members of the family said that "rumors" about Israel killing Palestinians to steal their organs have been circulating for a long time.

"I can't tell you if these rumors are true or not," the brother said.
"But in light of the investigative report in the Swedish newspaper, we are demanding an international commission of inquiry into the case."

If I understand the JP article correctly, the family lives in Imatin and is probably not the "relatives from Nablus" that is quoted in the AB-article.

So the conclusion at this point would be that the journalist did not talk to the direct family, who confirms that the rumor exists but they have no proof in the case.

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