If a lease lists a property manager as the owner's agent, to whom rent is to be paid, it's because the landlord has designated the property manager as his agent, to whom rent is to be paid.

I'm not sure how many times you need to be told that your grousing about the realtor and whether or not she committed some sort of license violation by also serving as property manager is irrelevant to either the validity of your lease or how much rent you go, but to emphasize:

It's not relevant.

It's not relevant.

It's not relevant.

It's not relevant.

Do you need it repeated a few more times, or is it sinking in?

I still can't see your agreement with your landlord about surrendering the premises and being released from the lease; again, if you're not able to resolve the matter without litigation, you should take a copy to court and attempt to prove that you complied with the agreement.