The most of sources I encountered (Vasmer, Mellory-Adams etc) assert the Russian word "voda" "вода" originates from the same PIE root as English word "water", i.e. from the PIE form u̯odr. This is allegedly supported by adjective водный which indicates that the PIE word had the r/n stem (-r in Nominative and -n in other cases, this is common for very archaic stems in PIE).
But recently I encountered with a person who seems to be very much confident that the word is a borrowing from proto-Germanic wađan (which gave also the English "wade"). He cites Winter's law and claims that the idea that voda is related to water is outdated.
So who is correct?