Quite why someone would not want to be found is beyond me. Are they really scared of something? And quite why the format of email addresses in a publicly funded organisation is such a big secret is also a mystery, albeit an amusing one. "I know but I won't tell you". Straight from the playground.
Real suggestion for the OP: If you can find one or more switchboard numbers (not necessarily customer services as they will not stray from their narrow script) - for example the front desk of a major building or one of the corporate offices - just call up and ask to be put through. Those operators will normally consult the standard intranet directory and if the person works for the outfit, they'll be listed. Customer Services won't necessarily do that - they'll try to solve your issue rather than follow your instruction.
Obviously if you don't have the required stratospheric security clearance, right handshake or aren't "in the know" you're not worthy enough to speak to a member of staff funded by your fares.