Last week I was near Campo Creek and still heard water flowing, but did not actually see it. Plenty of water in Cottonwood Creek which you will cross twice before Boulder Oaks. Judging by the water in Cottowood, Kitchen Creek should still have enough water(it feeds into Cottonwood). Hauser should still have plenty of water, Lake Morena Dam leaks like a sieve. I'll try and take a drive up Kitchen Creek tomorrow and have a look. Get back to you tomorrow. Depending on your schedule you should be able to find enough water.
I hike from my house to Lake Morena County Park(1 mile) and up to Kitchen Creek Rd. in about four to five hours alot. If you plan on staying near Lake Morena first night, you can get most the next section done before it heats up.