My instinct tells me that the OP's assumption is right and that the series is making a sort of a soft compromise, by making a tiny adjustment to the normal pronounciationpronunciation of the v, to allow for the sort-of-Germanic pronounciationpronunciation of the v (which sounds almost identical to the Spanish F).
@ukemi, what about Spanish words that end in "b", such as baobab, or in "z"? They're all voiced. Furthermore, I've been speaking Spanish my whole life (my mother tongue), in Buenos Aires, Argentina, and I don't pronounce or know anyone who pronounces voiced consonants at the end of a word as a p. Never have I heard anyone say "clup" for "club", or "kebap" for "kebab" (although I do see it written like that here in Switzerland).