They absolutely can (the dog owners) and the people who have to share the yard can report, not just to the landlord but to the local authority/EH as well.
The owners can:
Pick up poo several times a day.
Jet wash
Use suitable disinfectants/de-odorisering products
We have 3 dogs, we jet wash 3 times a week in summer, poo pick twice a day (more if someones done something truly awful and we spot it).
We use a product called Odorkill which comes in a variety of flavours, I've gone for peardrops but theres bubblegum, cherry, pine... probably more.
It is specifically designed for getting rid of the smell of urine and shite from concrete/wood etc.
There is no excuse with a shared yard, for there to be turds sat out, they should pick up immediately as they should on a walk.
Back in the dim and distant days of a shared yard, I had a spray bottle of deodoriser, so I'd go out with that and poo bag, dog would do the necessary, I'd pick up the poo and spray the wee if it was on the concrete part, or stick the hose on it if it was the grass bit.