I believe that there are some creditors (and I know not which) who simply will not accept settlement from borrowed funds as a matter of policy.
Purely thinking out loud, I guess, in this litigious age, there is a possibility that, at some time, a lender like Sprout will be hauled over the coals for unaffordable lending (after all, you are officially insolvent) and these creditors do not wish to be drawn into the melee by accepting settlements funded by such lenders.
On the other hand --- they could simply being, as you put it, 'parental' !
I am not qualified to give advice and can only state my opinions, based on my IVA experiences.