On reflection, I partly agree with you on this point.
Nobody can say for sure how many scots voted to stay in the uk that would have voted differently if they had known about brexit. However it's probably fair to assume that a decent number may well fall into this category. On that basis alone, they've got a case for another referendum.
If they vote to stay as part of the uk after another referendum, then it'll put to bed the whole brexit argument.
If they choose to stay as part of the uk (knowing what they know now) then they follow whatever path the uk takes.