What human and natural variables could prolong the Middle Passage across the Atlantic? How could delay make the voyage more dangerous for slaves and crew?

workers of lowell mills were greatly benefited for the waltham type of work which was more a paternalist kind, trying to protect the integrity of this little girls coming from small farmers and providing an adequate place of work, this in an effort to avoid the issues of bad place conditions and immorality that the people in bigger industrialized cities of great britain were experimenting.

the enslaved people onboard suffered from illness with some frequency

there are many answers to this question, such as a diplomat, ambassador, soldier, united nations employee, cia, etc.