Thx for trying to help. I had searched for "staff officer" before posting [;)] and only found posts about LCUs and air groups.
I just checked once more and now found something:
tm.asp?m=2391528
In this post some claim random leaders are taken from the leader list, others think they are generated outside that list.
In fact, they must be generated outside the list (like you said) - I have checked some names of "random leader" and they are not in the leader list.
So I cleaned my leader list of the hundreds of additional leaders I had added and fired up the scenario once more - but the staff REMFs were still there!
But alas, I think I have found the reason for my problem.
Since the beginning of my modding days I have had problems with saving the .csv files with Excel in a format that is compatible with witploadae.exe. I suspect this has to do with conversion issues from "text to columns" and/or between US and EU versions of Excel or whatever. So I am using OpenOffice which usually works ok to convert the csv in to column form and save the file in compatible format.
Now, acting on a hunch, I loaded my csv files with Excel instead of OpenOffice and did not convert text to columns - and compared the leader list with the csv file of unmodded DBB29-C.
And *drumroll* what did I discover:
My mod: [slot number],,0,0,0,0,0,0,0,0,0,0,0,0,,,,,,,,,,,,,
unmodded: [slot number],"",0,0,0,0,0,0,0,0,0,0,0,0,,,,,,,,,,,,,
There is "" missing in all unused leader slots.
After replacing ,, with ,"", I now have named random leaders where they belong!
Must have had something to do with data lost during the text to column conversion or else.
And it looks like random leaders are not taken from the leader list but use slots in the leader list.
So, I have reinstated most of my additional named leaders - problem solved.