So there was this thread some time ago but as we did agreed above, the HLC example is irrelevant (wording is different and the situation is different).
Now, the question is if we stay in line with the rules reference or we assume they are different even though there are no separate definition of a roll. Rules reference says "• Reroll: To reroll a die result, pick up the die and roll it again.". Because of those 2 words, I would say that you may use C3-PO with Flight Instructor, Lone Wolf and similar abilities.
I am wondering if there will be any FAQ for that...