This is fake for so many of the reasons you pointed out! Bleach water would have that tank good to go in a hurry. And I’m sure they’ve clean up piss and vomit before. In any case, why would they make an insurance claim and possibly raise their rates?

Having a baby blow shit up their back is FAR worse. You can’t take your time getting gloves and prepping and just hose the child down with bleach.