Hilife,
When did you last read FAR Part 29?
Specifically 29.927 Additional tests. (c) Lubrication system failure.
As the aircraft does not meet "extremely remote" i.e. 10-7 per AC 25-1309 as proven it is required to comply with the second
part of the paragraph which it also does not to this day.
The certification requirement overrules any BS that you put in the RFM.