The data is available from government agencies and aggregated on transparentcalifornia.com, which the article links to. Even if they omitted his name, the discovery process would take a casual web surfer two minutes at most.

Here are the top Bay Area public sector salaries for anyone whose job title includes "janitor"

http://transparentcalifornia.com/salaries/search/?q=Janitor&...

BART custodians are "system service workers" in their nomenclature

http://transparentcalifornia.com/salaries/search/?q=System+s...