Yes, the Goldstone commission, B'Tselem and Amnesty International sent investigators to the location to examine the scene and interview eyewitnesses. So did the newspapers. The BBC sent a crew to the scene and to the hospital (in Egypt, I think) and filmed Samar in a hospital bed. An eyewitness told an investigator that one of the soldiers had been sitting on top of the tank eating potato chips. The investigator found an Israeli potato chip bag on the scene.
I was going by the report you linked to, which quoted the father of the children allegedly killed, and unspecified statements by unnamed others. I wasn't aware of the Israeli potato chip bag, which of course proves everything.
I did find the BBC's story, which is a lot more balanced than your (or the UN's) account. A tragic occurrence by any measure, but as for the details of how it happened, just the Palestinians' word against the Israelis'.
Your solution is more dead Palestinians (which you don't care about), and more dead Israelis.
I'm not sure where you got that from. Where did I propose a solution, or claim not to care about dead Palestinians?
Gaza beach killings of boys. The Israeli government simply denies it all out of hand.
The killing was investigated by the Israeli government, who didn't deny it at all.