Hey all,
I've lived in Bucks County for my entire life, born and raised here. I grew up hearing stories of the Doanes. The general consensus is that they were rabid Tories, or British Loyalists. This was unusual in this area, because most of the settlers were either Dutch (thus often Rebels) or Quakers (thus pacifists). The stories I heard pretty much agreed that they stole from the populace and turned the goods over to the British. They are well known to have spied for the British as well. The Newtown treasury money was never recovered, but it's thought again that it was given to the British. Haycock Mountain is now covered in $1M++ homes. Trust me, those owners don't want people digging.
As for the brother that returned from Canada, he came back to file a lawsuit to collect a debt from a former neighbor (it was under $100, tells you how well off he was!). When he was recognized as a Doane, his court case was dismissed and he was essentially run out of town.
Frank B