The public doesn't have the right to know, since no law was broken. The engineer was identified by a "former state investigator [who] spoke on the condition that he not be identified because he was not authorized to speak."
We don't know that yet, do we?
"The F.C.C. recently closed its 17-month inquiry into the project, Street View, with a finding that Google broke no laws but had obstructed its investigation."
Even if we didn't, that's also a reason for not disclosing this person's identity: innocent until proven guilty.