The cave at the end of Lost Valley has two passages to the room at the back. One does require crawling on your hands and knees. The other, located to the right side, is actually a tight passage that you can walk through. When it appears to come to an end, you have to step down, squat slightly and shift over some and the passage resumes again above you. Then it's a very short (tight) walk to the falls room. Definitely take a good flashlight. In fact, take two! Not that far back, but it is still very, very dark! Turn off your flashlight when you're back in the falls room and see what I mean! As far as the virtual of Lost Valley, when I "found" it, I didn't have to go into the cave (although I did). I only had to post a photo of myself or my group at one of the many trail signs in the area. I'm not sure what the current requirements are.
Regarding Glory Hole, definitely a "Must Do"! The cache is so-so, but the Glory Hole is fantastic! Not a cave, but just an overhang in the bluffs where the stream has cut a hole in the ceiling, forming the "Glory Hole". Another beautiful area! I would wait until February or March for that one, though, after we've had the winter wet weather. -- ORR
"Wildness is a necessity." -- John Muir
"When you go to hide a geocache, think of the reason you are bringing people to that spot. If the only reason is for the geocache, then find a better spot." – briansnat