Do as Duke Pollard said. Get rid of all of the dual citizens who sit as MPs. According to reports Charran wasn't the only won.
Given that all of their votes will be illegal a constitutional crisis will result. So set up a provisional government consisting 50% of the PPP and the Coalition for an interim period until a new constitution is devised, voted in by this group and then subject to a referendum.
At some point after that the tribal wars can resume. Hopefully a new constitution and the fact that the PPP and the Coalition would have to cooperate with each other as neither would be able to over rule the other might blunt this ethnic angst somewhat.