Bus picks you up at the Palomar Trolley station. You'll see benches on the sidewalk located on Industrial Blvd where you're able to sit & wait.
This should help, download the shuttle schedule. https://www.jamulcasinosd.com/shuttles-group-tours/ Closest to Chula vista would be Palomar Street transit center.
Most likely the trolly to the el cajon transit station the busses are across the street from there.
Call the Casino
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