Suing Upstairs Neighbor For Toilet Leak

Location: Hawaii

My upstairs neighbor’s toilet (I live in a condo) leaked into my unit in April, it was clean water. I have video evidence from the plumber that it was leaking. I had to leave to go to the mainland the next day during the leak (it was slow), and when I came back the leak stopped so I was just going to replace the small part of drywall myself. However exactly one month later his toilet leaked again, this time it was wastewater. The neighbor replaced his wax ring and the leak stopped. After opening up the wall more I discovered the shower backboard is contaminated in urine and covered in black mold. The smell of urine and mold is overpowering my bathroom. And the mold is making me sick. I went after his insurance and they are trying to deny the claim, telling me to get my insurance involved, which my insurance also denied my claim, due to it being a continuous leak. I was advised to take him to court to pay for the damages, estimated to be 8-9k as of right now, but there could be more damage but it’s hard telling right now without taking out the shower. Hawai’i small claims limit is 5k, so I would have to take this to the district court. I’ve never taken anyone to court and I’m a little nervous, but I have literally everything documented and ready, and I’ve even sent him demand letters with no response. He is claiming he is not legally responsible for the damages. Does this seem like a case that I could “easily” win? Or if anyone has any advice please share! Thanks ????????