I'd be curious to know if there are nearby cameras that normally or frequently capture random cars but captured nothing around the time the suspect is likely to have fled.
Say there are three houses with cameras on a given street. Each camera is triggered by traffic 60% of the time. So, there's a 40% chance each camera does not capture a car driving by.
That means the probability that none of the cameras capture a car driving by is: 0.40 x 0.40 x 0.40 = 0.064 (6.4%).
Therefore, there's a 93.6% chance that at least one of the cameras captured a car driving by. So, if none of them captured a car, there's a pretty good chance that a car did not drive that way at that time.
I'm not saying LE could know the specific chance a camera would capture a car on a given night, but if a road has several cameras that sometimes capture cars, the chances that at least one of them captures a car driving by is quite good. If none of them captured a car, then there probably wasn't a car.
Extrapolate this to an entire neighborhood, and I find it quite surprising there isn't a clearer understanding of egress (unless there is behind the scenes).