Corrected entry: Merry and Pippin are brought by Treebeard to see Gandalf in Fangorn. Later, Aragorn, Legolas, and Gimli are told by Gandalf that the hobbits had been there. Then Aragorn mentions Gandalf's name, and he recalls that as being his name. Now, during the hobbits' prior meeting with Gandalf, one of them would have probably called him by his name, and therefore, he would have heard it before Aragorn gets there.
Corrected entry: It is rather astonishing that the German dubbed version is following Tolkien's guidelines for pronunciation more closely than the original English version. In the Appendixes to the novel (Appendix F, 'On Translation') Tolkien states that Sam's name is not of Hebraic origin but being short for 'Samwise' (an Anglosaxon word, Tolkien being lecturer for Anglosaxon and Old English) and therefore not to be pronounced similar to 'Sam' as being the abbreviation for 'Samuel'. Instead he would have had this name pronounced [sahm] (the 'a' like in British English 'fast'). Likewise goes for placenames as 'Isengard' ('Isen' rhyming with 'treason').