What qualifies as butterscotch
According to  this article from Wikipedia , your debate points 1 &amp; 2 could both be correct.


  Butterscotch is a type of confectionery whose primary ingredients are brown sugar and butter, although other ingredients such as corn syrup, cream, vanilla, and salt are part of some recipes. According to "Housewife's Corner" in an 1848 newspaper, the real recipe for "making Doncaster butterscotch is one pound of butter, one pound of sugar and a quarter of a pound of treacle, boiled together."


While I have never seen any recipe or reference that included adding liquor to butterscotch, and I wouldn't personally consider it essential, it's not too much of a stretch to think that someone has done it.