MP has been very generous in sharing his info.
I agree with MP that there are still many questions that need to be answered concerning how much work was actually done, or not done, on Lindner-marked guns sourced to other makers (Wm. Schaefer & son, Donn, etc.) The makers MP mentioned were just that - makers - so IMO it in not very likely that they just scratched their names on completed Lindner made guns looking to make a few bucks.
How far along in the finishing process these guns (or gun parts) were supplied to each maker is the one of many questions.