Charity?
Not charity at all, professional courtesy.
Nimmo's speciality is deep planetary structure susch as crustal isostacy and the thermal regime that influences convection. On that territory he's damn good.
I happen to feel he's looking at crustal fluids the wrong way, but as professionals I respect what he has done.
And yes, much more does need to be done on planetary and satellite magnetic fields, and there is good support in the science community in terms of skilled personnel and financial support.
Have patience and progress will be reported...