re: Would JPL risk
Much will depend on what I am sure will be an extremely detailed photographic analysis of the interior of the crater, including many 3-D shots, once the rover is in a position to peek in. I suspect there will be a lot of puttering around on the rim for a while, moving around the perimeter.
If the crater looks too steep to get out of (not likely, IMO), they may decide to proceed with other parts of the mission out on the plains, and then, as they did with Galileo, risk the rover in the crater toward the end of the mission life.