Theoretically, yes, he should have been extra-compensated. In reality.. no, most employers are looking at the "bottom line". However, I would request that your friend look into the 'higher ups' and ask why he wasn't compensated in kind for his temporary managerial duties.
There is a good possibility that his "higher ups" is the dirtbag that made him work, so he might have to be particularly nice in spite of his vehement feelings. Wow! This is really interesting, I'd appreciate any follow-ups!
GC.
Unless he organised this "upscale" before hand, I don't see him getting anything. When it became apparent that he would be doing more than he envisaged, he really should have spoken to his manager or HR department to discuss his working conditions, but you say this has been going on for several months. I don't know of any company or department that would backpay for that length of time.
They may give him a "good will gesture" but again I can't see if. Perhaps he should be having a chat with them now anyway to apply for the managerial which I am sure he has been doing well, and for the obvious salary increase that goes with it.
I cant really gove you an answer,but what I can give you is a way to a solution, that is you have to find the anglde that you relate to or peaks your interest. A good paper is one that people get drawn into because it reaches them ln some way.As for me WW11 to me, I think of the holocaust and the effect it had on the survivors, their families and those who stood by and did nothing until it was too late.