If you want rental premises repaired as a condition of your living in the premises, it's best to have the landlord make repairs as a condition of the lease and before you take occupancy. Otherwise, you open yourself up to this type of situation. Some people, you can take at their word. Others, you cannot.

The fact that a wall has been damaged by water does not of itself prove a health hazard to the occupants of a home, nor does it mean that any mold that may theoretically be contained within the wall space poses a risk to occupants without a means for spores to escape from the wall space into the living space.

A bad smell is not passing through now-dry drywall, unless there are gaps or holes in the drywall. If there is a bad smell without any openings into the wall space, consider whether it may be coming from other sources, such as carpet or carpet padding that was not properly cleaned and dried after the flooding.

If you're lucky, your local government will inspect the rental property and order any necessary repairs. The nature and quality of inspection of rental property varies significantly across the country, and even within a state or county.