What are our rights if were are moving out due to mold?

You don't owe the additional $550.  As for the security deposit, the security deposit is a cleaning deposit so the landlord cannot retain an amount beyond cleaning or repairing any damage to the apartment excluding any normal wear and tear.

In every lease there is an implied warranty of habitability which means the landlord is required to maintain the premises in a habitable condition by complying with state and local housing codes.  When there is a breach of the implied warranty of habitability, the tenant notifies the landlord and the landlord is required to respond within a reasonable time by making the necessary repairs.  If the landlord fails to respond within a reasonable time by making the necessary repairs, the tenant has the following options:  The tenant can make the repairs and deduct the cost from the rent or the tenant can move out and terminate the obligation to pay rent for the balance of the term of the lease or if the tenant stays on the premises, the tenant can withhold rent and defend against eviction.  Another alternative is to sue the landlord for breach of the implied warranty of habitability.  The mold is a health issue and constitutes a breach of the implied warranty of habitability.

You do not owe the $550 or any additional rent because when there is a breach of the implied warranty of habitability the tenant can move out and terminate the obligation to pay rent for the balance of the term of the lease.