When rescuers found the tent, they photographed it. In the photograph, I see the tent poles front and back with a burden of snow between them collapsing the tent in the middle. My intuition tells me that in that situation, the tent poles should be bent toward the middle ,but they are not. I can imagine thay they could remain vertical by tearing a hole in the canvas and poke through. Neither of these things happened. This suggests two other possibilities. My first idea is since the tent was made from two, the crush of snow separated the center seam, allowing the poles to stay up, but dumping snow within the tent. But, the rescuers did not find the inside packed with snow. My alternate idea is that the slab distributed snow on the top, the front flap side and the rear stove pipe vent side evenly. Imagine a slab slide much wider than the levelling shelf the tent was built on. This seems reasonable because everything would be buried at the same time with,evenly distributed pressure.
As a closing thought, there are those who argue against the slab slide because of the shallow slope, but I am reminded that the hikers footprints did not lead to the forest completely unobscured.