Raphide toxicity in Pothos plant
Perhaps someone else can answer this with more certainty, but I'd guess that because raphides are essentially sharp crystals that cause irritation-related symptoms, rather than toxic chemicals in the way one might usually think of them, that drinking the water wouldn't pose a problem (actually, I suppose the word "insoluble" might be a clue here). Raphides are defence against herbivory, and chewing raphide-containing leaves is what you want not to do (or not let your pets do).

Veterinary Toxicology p. 889 has more info.