You and I both know there won't be a 3rd party investigation, there is no organisation that exists that won't be accused of bias, one way or the other.
Let me explain my lense:
Israel are surrounded by millions of people who hate them, truly and in those nations they don't care about equal rights for women, religious freedom for minorities, equality for LGBT people, actual slavery etc, etc, their human rights records are actually disgusting. The Jews have a historical right to be in the area, this is undeniable, to me, and whilst the individuals in the IDF have acted brutally in the past and eroded all the trust you had in them for them they stand for a just cause - the existence of a people.
Hamas on the other hand have sworn to kill every jew on the planet and are aided and abetted by the Arab nations i mentioned above. in fact, the Arab nations don't give a single fuck for the people of Palestine, it's truly disgusting. I know it's a trope but they hate the people of Israel more than the love the children of Gaza.
That's my lense, as mentioned it will be a cold day in hell when i take anything Hamas said as the truth, given the brutality of their nature