Taking an in season bitch out for a walk is irresponsible full stop.

I don't know what peeing inside has to do with it. I would question the wisdom of having a dog if you don't have a garden to use - particuarly one that apparently needs so much exercise. The fact that the owner appears more responsible than other owners around does not make them responsible... just marginally more responsible than others...

As for her temperament... if you are breeding you cannot afford to make excuses for poor temperament, even if you think there is a valid reason for it. ONLY dogs with EXEMPLERARY temperaments should be used for breeding.... NO exceptions.