The date 73,000ya is pretty close to the 74,000ya date for the eruption of Toba leaving a crater 16 x 65 miles. I wonder if these events were somehow connected. Was the earth in a particularly restless mode in that millenia?
Apparently after a major Alaskan earthquake in the 1900s there was a tsunami that ran 1,000 feet high up a fiord.
The Alaskan event you mentioned was at Lituya Bay -- a tributary to the fjord suffered a massive ice landslide, which blooped right into the water, and sent a big wave in both directions. There were actually a number of campers along the Bay, some of whom survived the event. The debris line reached inland to 1700 feet elevation (roughly a third of a mile). There was no significant tsunami in the Pacific, AFAIK.