It has been a while since I played the game but I'll list all the Board of Directors and where they are.  :)

Joseph Tangye – Toronto

Felix Baumeister – Cape Town

Alex Fletcher – Zurich

Whitney Baumeister – Wellington

Dieter Baumeister – Tokyo

Evangeline Baumeister – San Francisco

Make sure to seat those guitar girls as early as possible.  The grandmas can be very patient so there is no need to seat them right away.  Like the regular girls, you get bonus points if you seat grandmas or regular guys next to the guitar girls.  The guitar girls have as much patience as the regular girls but be sure not to leave them unattended for too long.  Otherwise, they start playing their guitars and making their companions seated next to them annoyed.

The above should help you to make the goal at least.  :)