Well, not 100% certain, but if you're talking about the group name of animals (which has to follow the rule that the collective noun describes what the animals do), you could argue the point for 'a wriggling of maggots', 'a chewing of maggots' etc.
A group of maggots is called a "maggot mass" or a "maggot congregation."
Scoleciphobia, Fear of maggots or worms
Baby houseflies are called maggots. When flies are born they become larva and then they become maggots. The maggot will then eventually become a fly.
The name is a collacine
Baby flies are called maggot.
maggots
Maggots They can also be called 'cadets'
Grubs
All baby flies are called maggots.
They are commonly called maggots (or gentles).
Larvae of a fly are called maggots. When a house pet gets a wound it can be infested with maggots if not treated in time. Flies get attracted to such open wounds and lay eggs in it which eventually produce maggots.
The book was written at the age of nine by Jacqueline Wilson called Meet the Maggots