I'm not familiar with Oakland, but I'd be heading over to Alameda.
At the end of Webster, go left on Central.
Right on Westline ( right after park).
Cross- Drawbridge onto Bay Farm-becomes Doolittle
R-Hesperian-becomes Union City Blvd-Becomes Ardenwood in Fremont
If you take a left on Paseo Padre, it will take you over I-880 to the east side of Fremont.
Where is he going in Fremont? He might just get on BART and take it there.