I haven't rewatched Question Time and I admit I wasn't giving it my full attention but while I remember the statement that the vote for the referendum bill was 6:1 in favour of the bill, I don't recall them mentioned they believed it was binding. I may have missed it.

You did.
I will transcribe their statements if you like, but it is all available on BBC iPlayer.
It is the first question, and the first two respondents.