It is not bad luck or an accident, it is negligence.

Also, the home inspector missing it probably hurts my chances even more, but the home inspector was extremely negligent and missed 5-6 major issues with the property.

Jacob, Typically the downstairs owner would have to establish that you were negligent in order for your liability coverage to kick in for repairs to his unit. 

If it is tenant negligence, then you can absolutely charge them for the repair.

It does not prevent the owner from a subsequent claim against owner if there is proven negligence.  

That's interesting, you either have a negligent contractor or a tenant causing damages.2.

And yes, vinyl is more energy efficient but in terms of "dollars and sense", the actual energy dollars saved per year is negligible and doesn't necessarily justify the the trade off for longevity.

Then a liability claim happens and Doe,LLC was negligent...John Doe’s Policy listing Doe,LLC would not defend or pay damages as John Doe was not negligent in the claim.

Who owns the appliances generally determines who pays unless the tenant was extremely negligent in using your appliances.

I am sure the civil action will be expensive for all.From what I read in the attached below you will need to be vigilant as negligence could be VERY expensive . https://www.peoples-law.org/lead-paint-law-rights-and-obligations-renters-and-property-owners