Yes, the Vishwas are the same as the Vishwadevas. This excerpt from the Markandeya Purana describes how when Vishwamitra took Harishchandra's kingdom from him, five of the Vishwadevas spoke out, and Vishwamitra put a curse on them to be born as humans:
But then spoke five Vishwadevas in pity, "This Vishwamitra is very wicked; what worlds will he obtain, who has uprooted this best of sacrificers from his throne? By whose funeral ceremony further shall the soma juice expressed at the great sacrifice by purified, by drinking which shall we reach the exhilaration that is preceded by incantations?" ...
Having heard their remark, the sage of the Kaushika race, exceedingly enraged, cursed them -- "Ye shall all assume human form." And propitiated by them, the great Muni added, "Although in human form, ye shall have no offspring. There shall be neither marriage nor wives for you, nor hostility: freed from love and anger ye shall be gods again." Thereupon those gods descended to the mansion of the Kurus with their own portions; they were born from the womb of Drauapdi as the five grandchildren of Pandu. Hence the five heroic Pandaveyas did not take to themselves wives, through the curse of that great Muni.
In any case, the chapter you're quoting may have either a transmission error or a translation error, because all other references to the Upapandavas don't mention Draupadi having a son named "Nakula". They just mention five sons: Prativindhya, Sutasoma, Srutakarman, Satanika, and Srutasena. See this chapter of the Adi Parva of the Mahabharata, this chapter of the Vana Parva, etc.