i think you should pursue it... you definitely have a case, its almost black and white.... even if u decide u don't want to pursue it, at least leak the 'discrimination' word and make him sweat a bit ... but if it were me, i would be looking after number 1 and my finances.... this guy has clearly screwed you over...

if you decide to go further:
start making notes of EVERY conversation email etc etc, and the phonecalls regarding interviews... document EVERYTHING.

just out of interest, what's your gut feeling, do u want to pursue or let it go?