No, you do not "need" to turn to theology. There are plenty of explanations that do not involve invoking myths.
> all death is ultimately caused by sin
So the pedestrian was secretly a pedophile? That's a pretty strange explanation...
I'd say in this case the blame likely rests on city planners, for creating situations in which travelers can collide.
So your options in terms of the originating cause are either to turn to religion for a philosophical answer, or to say "I don't know and we may never know".
> all death is ultimately caused by sin
So unless you're saying the big bang was a sin, your comment does not follow the parent's logic.
Christians would say God, scientists would say the big bang (or something even before that, it's basically unknowable). They're not even mutually exclusive as you could say that the big bang is the means by which God created the universe, or any other origination story you can come up with.
The uncaused cause says nothing about later cause-effect pairs, only the originating cause.
Care to explain this statement to me then? Seems pretty clear to me, but you seem to be interpreting it very differently.
I think the parent edited their original comment as there was some stuff in there directly referencing God as the original cause before and that seems to be gone now.