@farmerman,
Actually he was buried (in early January already) in the Teutonic College cemetery within Vatican City State.
And this cemetery is the cemetery of the parish church within the Vatican sate (St. Anna) - so it wasn't the Pope's but the pastor's of St. Anna, Father Bruno Silvestrini, (who had already dedicated the Nativity Scene at Christmas to Willy).
The costs of his funeral were covered by a German-speaking family, the funeral was held in the chapel of the Teutonic Cemetery, and Willy was buried in this old Germanic cemetery on January 9.
The Collegio Teutonico (German College), St. Anna and the cemetery are located in Italy and one of the properties which form part of the territory of Holy See but which are located outside the confines of Vatican City boundaries.)