Not understanding the difficulty here?
When you say you "ice picked" the valley pan, are you doing this through the CDR hole? I always punched them out from the bottom, which requires removal of the valley pan, I always used new. Not saying you cant do it from the hole, but I am wondering what kind of holes you were able to get through that small hole at an awkward position in the engine bay, especially under the turbo?
This banks drain tube is used on thousands of trucks, if you have it sealed up at the turbo flange, and inserted in the valley pan with a grommet, then I don't understand how your having such trouble. Did you ever leak test the tube itself? if it is pushing oil back up past the grommet, then your valley pan is not draining enough oil....
I dont understand the whole reinventing the wheel thought process here? Maybe I'm the only one?