How did 'Rollover Jango' and 'Iron Fist Fullbody' become Ms. Hina's subordinates? We all know that Iron Fist Fullbody was demoted after the incident at Baratie Restaurant, and Jango was a famous pirate with a bounty of 9,000,000 Beris. 



So how did they manage to get into Grand Line under Ms. Hina?
I tried to find about it and it took me a while but I got it, it's an interesting story presented here. As a summery:


Jango wakes up, chased after by 'Usopp Police Squad'.
Takes a small boat, passed 'Captain Morgan', both asleep.
New island, marines searching for him.
Takes a disguise, enters a dancing contest.
Jango is the winner, Fullbody is first runner-up.
Island attacked by 'Caption Yurikaa' leading 'Tulip Pirates'.
Jango runs, Fullbody fights.
A girl is taken hostage, Fullbody is defeated.
Jango returns to save his 'Brother', both defeat those pirates.
Fullbody captures Jango, degree 'Death by Hanging', Fullbody objects.
Decision overturned, Fullbody got a demotion.
Both agree to be hypnotized, to forget about their friendship.
Hina appears, decision changes, they decide to follow her.
Both enlist into Marine HQ with 'Mop in hand'.