Was thinking about spraying expandable foam in some areas but I don’t what to blow the thing apart.
Also don’t know if spraying foam in the wrong areas will put of balance.
Thats a BIG no no ! ( NO expandable foam ! )
And YES ... thats a BIG yes yes ! It WILL throw off the balance BIG time !
get some CA glue for a simple , fast fix .
Or , you could use some epoxy and fix her up the right way . Lightly buff up the plastic , then apply a thick glob ( just don't get rediculous though ) of epoxy , wiggle the cracks just a little so that the epoxy gets in between the cracks and let cure . When done , sand to a SMOOTH finish .