My story:
after being 0/20 i somewhat gave up on camping him for a while, a long while. Few months later got 75 bard, then 66 nin and ppl in my ls needed some help on a few items. Got a bit tired of exp so i said sure, my friend is almost 100 cooking and needed the katana for cooking skill+3, so we're camping the nm wich seems to have the same pop requirements as rogberry, i believe it was sazberry. Anyways i stay for about an hour and every1 else left, i decide to check on Rogberry but he wasnt up, yet no campers >.> So i run back and i see a nin getting chased by Sazberry but somehow didnt link the entire map, he was 2 rooms away from pop area, so i claim and hold him, i knew as 75 thief i had no chance against his mijin gakure, so i kept sleep bolting him until caledor (DRG) and trazzalene (THF) show up to help, a nearby nin was friendly enough to help as well, after it was down to about 50% everyone unloaded on it, in about 2 secs is life went down to 5% and he never 2hrd but no drop.
Since we were there we decided to hang out at rogberrys camp for a bit, thf needed test and what better way to get it. it was almost exactly 1hr after killing ph's that rogberry popped (coincidence?) yet drg was the only one in the room, me and other thf went coffer hunting, so we flee back and start pounding on him. took secs to kill and finally 1/21.
Cant thank my ls mates enough for ur help and long hours of camping. And to all of you camping this thing, good luck, happy hunting and if and when u do get this, the rush of the drop is impossible to gauge. ^^