Tenant's Washer Machine Hose Causes Damage and MOLD

[Amanda Lee]

Hello. At my 2/1.5 duplex, have washer and dryer connections. The Tenants bought a used washer and dryer. Got a call from them at 9pm saying there is a leak and mold is growing behind the washer and dryer. I told them to not "disturb" the area, and to send me a pic to text to my handyman/GC. Never got a pic from them but walked into this:

[I almost had a heart attack!]

My GC (who is freakin awesome) came out and determined it was due to the washer machine hose and possibly the faucet valves was not fully turned on. Apparently they did not get new hoses when they got the washer.

[We think the left one is the culprit]

How to I handle the Tenant since I am not responsible for their appliances? I know this needs to be in writing, etc. But is there a letter or template out there I can use? It is stated in my lease that I am not responsible for damage cause by the Tenant's appliances, blah blah blah.

I am in Tennessee.

Thanks!