There are lots of breakaway collars for dogs... there's just 2 d-rings on it for on-leash.

Both of my dogs wear rolled leather collars that I'm careful to fit them. They both wear collars, because I feel them getting out/lost is much more eminent than any situation like this. They don't go outside alone, anyhoo.

I'm glad both of your pups are ok! That definitely sounds like it was scary.