This is one of those things I didn't want to learn about... let's talk about Pennsylvania's laws surrounding car accidents.  Apparently, not bothering to call the insurance back is a viable strategy... that's what I'm seeing.  If they don't respond they might lose their insurance, but if fault cannot be established then Pennsylvania treats it as no fault.  What does that mean?  It means I'm f'd and get to pay my deductible.  It also means that because I don't have rental coverage, I get to go without a car while repairs are going on or I get to pay for that too.

I strongly encourage you to not be at the wrong place at the wrong time when someone decides they want to abruptly be in your lane - 0/10