My team ran into a similar issue and our ‘fix’ was different enough that I hope it helps others trying to load their raytraced scene up.
We loaded up a blank scene, set the viewport to wireframe mode (NOTE If you have more than one viewport, set them all to wireframe or unlit, the point is to not be in lit or detailed lighting mode)
We then loaded up our level that was causing the crashes and found two of the dozens of lights we had did NOT have raytracing checked on, while others did. Checking raytracing on those two lights on and then switching the viewport to LIT worked.