My husband, who is a member of Unite, works for BA but is not CC, did know about the survey, but hadn't heard the result. He doesn't know any CC, and didn't get the survey himself, so presumably other colleagues may have received it and there was conversation about it. That would mean it was sent out wider than just CC. The actual report does infer that, as it refers in it's conclusion in the first line '
Almost one in every two workers at British Airways has been bullied' not just CC.
I know a bit about surveys, methodology, and how to draw conclusions from statistics, and the union's conclusion extrapolates that just because 75% of
voluntary respondents had been or had witnessed bullying, that percentage can be deemed for the whole workforce, is just plain wrong.
If there had been a proportional issue of surveys amongst all departments, and
everybody surveyed had to respond, then that kind of extrapolation could be justified, but not otherwise.
It's also fairly easy to devise a survey, and ask the appropriate questions, to get the replies you want, to 'prove' something that you wanted to prove at the outset. We know Unite have been accusing BA of bullying for some time, and asking for the very things they set out in the recommendations at the end, which are -
Bullying to be taken seriously at British Airways
An end to the culture of intimidation, imposition and union busting
Recognition of union reps and facilities time
An independent review of sackings of crew and reps
A new corporate strategy that treats all members of staff equally and fairly and where all have a role to play and contribution to make to the business
Pity there wasn't a question as to whether staff had been felt bullied by striking CC (and the union) when they hadn't themselves gone on strike 
Maybe that accounts for some of the 'other' boxes ticked.
I doubt BA will pay it much attention, but it's something Unite can quote to the media as part of it's
PR.