This is a sentence meaning and if they are synonymous with each other(''least of all'' to ''let alone'').
The leaders of the Harakiri Gang do not want to go to school, least of all their members.
The leaders of the Harakiri Gang do not want to go to school, let alone their members.
If a statement is somehow negative, sometimes, we include 'least of all' and 'let alone' depending on the context, right? My question is, are the bold letters in the highlighted sentences above, used appropriately and are theysynonymous.