I'm a Delta retiree....and I wanted to respond to your question with some information.
If you are a Facebook person, there is a group Carry-On Rescue Transport that has several airline employees on it..we help transport small pets that will fit under the seat on a space available basis.
I would suggest posting both in Pilots n Paws and this Facebook page. I and other airline employees read both and will try to assist when we can. Our travel privileges though are space available so this does require flexibility on everyone's part. I also notice more nonstops (obviously the desired way) out of San Francisco than Oakland, so wonder if you would be able to get the pets to San Francisco.
Hope this information helps, feel free to contact me if I can assist. (unfortunately I'm in Tampa, Florida though..)