Flood damage: a penny for your thoughts

[Sara C.]

Would love any ideas on how to handle flood damage. 

What happened:

Tenants moved in at the beginning of May, brought their own washer/dryer and had a Lowe's contractor install it. The contractor hooked up the drain line incorrectly and for the past 4 months, the washer has been draining into a wall cavity and crawlspace. This was discovered last Thursday when they had a small flood in the laundry room. I had a flood remediation company out yesterday and they found damage in the crawl and water beneath the kitchen tile (shares a wall with the laundry room), the laundry room itself including drywall and a den adjacent to it. The tenants have been complaining of humidity so it's all making sense now. It's going to be a huge project to repair and tenants will likely need to move out while the work is being done. 

My question: do you think this is worth pursuing with Lowe's? Otherwise, I'm going to be taking out an insurance claim. My tenant is reasonable and understands their responsibility in this, but the repair cost will be too high to expect them to contribute significantly.