Mr Mark,
We have been on that section of S-22 several times. That by far, is the worst section of road, in So Cal. And, what's amazing, it's a well traveled road. It's not something that's only used say, once a month or less. That road, is traveled, during the "desert" season, by thousands and thousands coming from points north of S-22 and even south and west of that intersection.
We used to access "Truckhaven" area of Jeeping via that road, then hit 86 north to North Marina and then turn west again. And yes, I almost have no doubt that your front wheels left earth. Ours did, more than once. I've seen many front wheels on motorhomes depart earth on that section.
I'm really surprised that CAL TRANS has not been sued for damage to multiple vehicles and has not repaired it.
Anyway, you now know where it is, and what kind of conditions are presented when you traverse it. I now slow way, way down, when I approach it, from both directions. Good thing you did no damage.
Scott