Does the interpretation of the noble verse: "So for what you have enjoyed from them thereof, give them their due compensation as an obligation" (An-Nisa: 24) refer to the dowry (mahr), or to the maintenance (nafaqah)?

The verse is not about maintenance, but about the dowry or bridal-money. Its meaning is that the dowry is not fully due except upon consummation. Thus, "enjoyment" refers to intercourse, and "wages" refers to dowries. The verse does not imply the permissibility of mut'ah marriage, because its context indicates a valid marriage by which "you seek women, in wedlock, not in fornication." Mut'ah marriage has been abrogated and forbidden, and the proofs of its prohibition in the Qur’an and Sunnah are clear.