Don, lots of soldiers testified at the time.
Virtually everyone has to serve so you get fruitloop and rabid politicos ex-soldiers.
Only a tiny number have claimed bad things and not until long after.

everyone who criticises or exposes any Israeli crime, as in the case of Sabra/Shatila, of commission or omission, is a liar, a bigot, an antisemite, or all three?

We KNOW that there is an industry out there making up lies about Israel.
Those people who "SAW" the Jenin massacre WERE liars because it never happened.