Really?
Methersgate, do you really believe what you wrote?:
...never, ever, opium or any other illicit substances, neither grown, nor traded, nor carried.
My old memory cannot recall the title but a book I read some years ago suggested that Swires did in fact do what you say they didn't but were highly successful in not getting caught.
I do, however, as do you, give them credit for what they have done since the late 1860's - with, of course, one glaring episode that did them no credit whatsoever.