Nope, payment has always been back at the original station. At any rate having done a LOT of passenger missions I've never got payment anywhere other than the original start point.
For example, it is possible to get to your destination, do all that, come back to the start and turn on silent running to avoid a scan. You then miss the letter box because you're rushing and nearly kill yourself on the side of the station.
The passengers get all cross, demand to be let off and you don't get a penny. Otherwise what's to stop you taking the money in the middle of nowhere and ejecting the punters?
Don't ask me how I know, I just do
