Upstairs leaking causing water damage...

[Lee Hao]

Hi guys, first time post here. I have a first floor condo rental. Yesterday night, 2nd flr unit water heater was broken and dumped all the water to my unit. So I got wet carpet, water heater closet all wet, and wet living room walls. The 2nd flr owner called me and offered to fix my water closet by himself. But there are more than water closet to fix including electrical wiring inside the walls. So I told them I would rather have them file insurance claim and have properly licensed contractors do the work. In parallel, HOA sent an inspector to inspect the damage, but 2nd flr unit already replaced everything up today. So the inspector said all he can say is water in my unit is from upstairs, but he cannot tell for sure if it was pipes responsible by HOA or 2nd flr unit's water heater that has caused my water damage. Now both HOA and 2nd flr unit are turning their back on me. My tenant seems ok for now. But I want to fix everything quick before more moisture damage. What I want to get advice here is what options I have to get the responsible party to pay my repair cost. I have asked the 2nd flr owner to file insurance claim. I also asked HOA to either help me mediate or clarify whose fault it is (HOA vs 2nd flr owner). But if they just ignore my requests, what should I do to get them do the right thing?

Thanks!

Lee