I think Honda hadn't close th door to sold engine only to Oak.
It's the only competitive solution. Unless they could persuade Porsche to lease them some old RS Spyder engines
just joking...
But indeed it's the only solution, Toyota totally impossible, Zytek or Mazda wouldn't be better then Judd, the other way around and no one will start a LMP1 engine program when it will become obsolete by the end of 2013...