This is a hard conversation to balance. You were right to state OP added more to the scenario than is known. But people tend to react defensively (which turns into offense often) when they’re personally called on as you did there.

The nonviolent thing to do, I am honk, is to simply describe what is actually known and point out how the accounts differ.

For what it’s worth, none of us were there and it sounds like definitive information is lacking. My hope is for this to be valuable used to ensure safer driving for everyone (autonomous or not).