"Yes, but in those cases the idea is that you dive through the wave and come out the back side. "
NO. The idea is to dive under the wave. You cannot dive through a wave of that size even if it isn't a tsunami. You must either get over the wave by going to higher ground, or get under the wave by diving under it.
Even a big wave, though, is going to pass by and allow you to surface in a relatively calm lull. A tsunami wave is going to continue to pound you into the shoreline as it drags you into land, because no lull follows the initial wave.
Have you seen any of the eyewitness videos? (post #109)