I wouldn't have given two shits about the cars in the underground parking garage... and why that would be happening in an "estate" where an ordinary 'guy' uses military time to decribe 8PM, I have no clue.
I would have packed my son up and split immediately letting the dipshit dispatcher know I was rolling and what route I'd be taking.
Sounds like there's a whole lot going on, and more of the story to unfold, but the number one priority is your son. Godspeed.
I do have some insight on kids stopping their breathing while sleeping as I have a friend with two sons, both young. You don't say what age he is but if he is as young as I think he is, it may pass in time.
It's tough for a parent to deal with, that's for sure.