I had the idea that foreign visitors are exempt from this tax when they pay with a foreign credit card, still my hotel manager insists I need to pay this tax. Since there is a language barrier between us, I'm looking for a reference in Spanish I can point him to (if I'm indeed correct).
¡Sí! Had to learn how to make google search Spanish (latin america) pages first.
Here's a news article about it: Argentina devolverá IVA por hotel para atraer turistas extranjeros
And here's the official bulletin from the government: Administración Federal de Ingresos Públicos y Ministerio de Turismo IMPUESTO AL VALOR AGREGADO.
Hopefully those two articles should be enough to explain it to him in Spanish.