Many fans of the game believe that Alvin is actually the Grand Master of the Order, Jacques de Aldersberg. When the fight between the elves under Toruviel and the Order of the Flaming Rose erupts in full force in the village of Murky Waters, Alvin teleports himself away because he is frightened by an elven warrior. Alvin's ability to teleport himself through time and space stems from the fact that he is a source. It is widely theorized that he flees to the past, perhaps back to where he was raised and, ultimately incorporates what he had learned with Geralt, accepting his perceived fate and became the Grand Master.
Clues that speak to this hypothesis include the dimeritium pendant Alvin wears. Alvin, the boy has one as does the Grand Master; only difference is that Aldersberg's amulet shows years of wear. Another hint lies in the mention that Alvin's favourite game is "kill the elf" where he always plays the Grand Master and wins. Also, when Jacques' group comes to the aid of the refugees in the Swamp Cemetery (Chapter V), Jacques tells Geralt that he was returning a favour by saving the witcher's life, possibly referring to Geralt rescuing Alvin from kidnappers in Chapters I and III, killing the Devourer who attacks Alvin in Chapter IV or slaughtering the barghests hunting Alvin at the beginning of Chapter I. In the same conversation, Jacques is suspiciously quick to accuse Geralt of preachiness — not a common trait of Geralt's, but one he must show when acting as a father-figure to Alvin. Jacques also mentions that he knows about Geralt from "a source", which could be wordplay hinting at his past.
At the end of the game, if the King of the Wild Hunt is allowed to take Jacques de Aldersberg's soul, he tells Geralt that he knew this soul under another name as well, possibly pointing to Alvin, although his name is not explicitly uttered. Also, all of the lessons given to Alvin by Geralt appear to have had a major influence on the Aldersberg's expressed views during the endgame speeches.