Maybe I'm misreading the situation, but looks to me as if you dropped the ball. 

@Al Ball I am an agent of 22 years in another market.

With the notice and ss list, the ball is in their court and you can rest easy knowing you did what you could.  

I agree most of them have been conservative offers but not low balled any of them.

And if you have a central office on location, you could have balls, water guns etc. available for checkout.

I'll admit, most of them are low ball offers, but it just doesn't make sense at a higher price.

Clearly someone dropped the ball I don't know who.

The right thing for Tenant B to do is start paying his share by splitting the water bill.It sounds like he will refuse, so you move to Plan B and tell him that because he refuses to play ball, you will not be renewing his lease when it ends.

Also, do you have an agent or agents that will submit these numerous low-ball offers?

they're out like the fat kid in 5th grade dodge ball!