As far as I know, nobody's treated the question in any novel sense, at least in English, since Henk Wesseling wrote an article in the Journal of African History in 1981. (Paywall, sorry) Wesseling's basic points--focused on a reading through the Congo case, where Dutch mercantile interests were engaged--note that the Dutch did not seek any part of the African settlement because they were already in an expansionist phase in SE Asia, protecting their interests there. Indeed, the Dutch had divested themselves of their last claim in Africa in 1872 with the cession of rights on the Gold Coast for a payment from Britain. In effect, as a colonial power the Dutch were "saturated" (in Wesseling's parlance) in the East Indies both administratively and in terms of pacification, and although there were commercial interests that watched the situation with Africa, the political will did not exist for expanding into Africa, and the openings they might pursue for a new sphere of influence would have been small in the best of circumstances. The British had legal control, by treaty, of most places that had been Dutch; even their suzerainty and influence over the nominally independent Boer Republics in South Africa was tacitly accepted (a point Martin Bossenbroek makes in his work on the Boer War and Dutch policy dualism that was publicly sympathetic to the Boers but politically in line with the British, as his chapter in Keith Wilson's The International Impact of the Boer War indicates). In any case, it was not really worth antagonizing neighbors for very little gain, if any, and such antagonism could easily manifest in other nations' disregard for broad Dutch claims in the archipelago.

So the Dutch government pushed for freer trade in areas where they had significant interests (like the Congo basin) and earnestly believed Leopold II when he promised it to them. (As for their response to his Association's actual activities to lock those merchants out later, I do not know.) African empire was, based on his reading of Dutch policy documents from the era, something they paid attention to but deliberately did not pursue in light of their more important position in Asia. That decision did not apparently meet with any major dissent from the public.

When I am back on campus, I will page through Wim van den Doel's Zover de Wereld Strekt (2011) and see if he adds anything to this point or has come up with a new interpretation, but I just got my copy of the book literally last week so I have not read it through yet. (Why it took so long for me to get a copy is another story.)

[edit: fixed a word choice]