I think that guy's boat will be intact for 30 seconds max in a Tsunami.
Why do you think that? Did you watch the video? I´m no engineer but to me it seem sturdy built. Rigid frame of boxes and double hull with foam filling in between.
A tsunami will subject the boat to fast moving debris like a stop sign, broken bicycles, trees parts, garden furniture, etc. The boat also has to withstand a hard impact against, for example, a building with rebar sticking out or the neighbor's wrought iron gate. This boat needs to survive all of that completely 100% of the time. I don't even believe my tiny waterproof flashlight could withstand that abuse.