Good links.
The world net daily article is agitprop and offers no evidence whatsoever other than a sniper "could have" shot the boy. As it's "evidence" to support the claims made therein it has to reach all the way back to 1948 to show that Arabs hate Jews and therefore the claims that a Palestinian
could have shot the boy must be given weight. Funny, but not something I would try in a court of law.
The article regarding the German television report is not specific and doesn't even detail WHY ARD concluded that Palestinians shot the boy.
Anything is possible. But nothing in these articles can be considered conclusive by any stretch of the imagination.