Originally Posted by NightIP

If the report is accurate, the left fuel selector was pointed to draw from the left tank (tank-to-engine), but wasn't engaged into the detent. This means that it was still in the crossfeed position, with the left engine running off of the right tank. When the pilot moved the right fuel selector to the left tank (full of fuel), the right engine quit as well.

I believe, and please someone correct me if I'm wrong, but you can't have two engines in crossfeed at one time. With the left engine already in crossfeed (with the pilot unaware), the right engine wouldn't accept a crossfeed to the left tank. I can't tell you why the engines started on the ground with the fuel in the tank, but these engines are very finicky. Perhaps they'd run while on a level ramp, but in the air in a nose-down pitch attitude they wouldn't. Nothing conclusive can be drawn from this yet.