did you pick up the grenades before the controlpoint?
i guess you should not to make this work?
and one should go with nothing but gun in inventory to pick up as much grenades as possible because you can not go to jen in the meantime.
i will check that out.
edit: i think it won't work without the quest because there is no control-point when you are out of it.
the controlpoint must be somewhere after killing afran.