If I was carefully looking for prior art to invalidate the patent, I'd look at Verizon's patent portfolio:
https://en.m.wikipedia.org/wiki/Hum_(system)
Their Hum product seems to do exactly what the patent troll claims to own a patent on. It plugs into the OBD2 port and calls emergency services after a collision.
Also, Nissan patented something very similar in 2004:
US Patent for Vehicle emergency notification system and related method Patent (Patent # 7,323,972)