Liability Repairs for Tenants?

Hello,
I have a tenant that overflowed their toilet and caused water damage to the unit below them. The owner of the unit below them then had repairs done without the consent or knowledge of my tenants, and without them having the opportunity to seek multiple bids. The owner of that unit is now asking them to pay the bill which is nearly 3 times the insurance estimates.

Do my tenants legally have to pay this?

Thanks!

It would have been polite for the lower tenant to work with the upper one's insurance company and seek estimates. But that tenant is not bound by the insurance. It is not her/his insurance nor was s/he the liable party. S/He is free to have the work done and bill your tenant for the damage caused. Your tenant is free to have their insurance company contact the lower tenant and negotiate a fair price. Since your tenant caused this and their insurance company is responsible, not yours or you, why are you getting involved? You are not at fault, your tenants are. (Unless you had a plumbing problem that you failed to repair.) Let them work this problem out themselves.

Thank you! I'm only involved because the lower resident is trying to charge my tenant (it's a condo) an Exorbitant amount of money for the repairs - and I think she is trying to rip them off. She has been a problem in the building for some time, and has done similar things before. Seems like she should have been required to allow my tenants the opportunity to find a reasonable bid, and arrange the repairs - rather than expecting a blank check. My tenant has been totally cooperative and has already paid $1500 toward the cleanup costs, so this was unnecessary. I also have info that implies that she had additional work done that she is trying to bill for. (I have no solid proof).

Anyhow, that's the situation - and I fear my tenant will move out if they get ripped off. So I guess that is my priomary interest in the outcome.

Thanks if you have any additional input!