Thank you OP and sorry that your daughter and you have had to suffer because of this dangerous and irresponsible policy. 
I hope you have had interest from the various UK charity commissions (the regulators of charities) on this new policy and how terribly Girl Guides UK handled this and how it fits in with the charity’s legal stated aims (technically called ‘charitable objects’) of what GGUK exists to do?
What kind of healthy charity or voluntary organisation doesn’t even consult with its members before introducing policies contrary to normal safeguarding good practice? Let alone why they would even consider adopting policies contrary their own charitable objectives, which are about supporting girls and women? Then to make it worse, what kind of healthy charity kicks out its volunteers (and effectively their kids it seems)....just for asking questions about their policy that members were not ever allowed to give a view on or ask about in the first place?
It’s just so boneheaded. The equality policy also doesn’t even support girls or young women in Guiding who do want to socially transition to a boy/young man’s identity. (The policy talks about how they will need to leave GGUK ultimately because of their gender identification.) yet kids under 18 can’t get GRCs so any ‘male’ identity these young people adopt, is just courtesy, there is no legal sense in which these vulnerable children and teenagers are ever NOT still girls and women just as much as the day they were born and however they identify ... so why kick them out?
How does it not break the ethos that ‘GGUK supports girls and women’ to kick them out solely for having identity confusion or gender issues or adopting a certain persona (whilst still remaining all the while a girl child like any other girl)?
It a policy led by male entitlement and s encouraging an ‘ahead of the law’ 
approach to the identity issues that girls and young women may have, and a weirdly permissive approach to biologically-male adult access to young girls and young women, that actually works against their interests. The GGUK Trustees should be ashamed of themselves.
Quote from the Daily Mail article:
Her dispute with the Guides began in June 2018 when, along with fellow leader Helen Watts, her objections to the transgender policy were secretly reported to the Girlguiding leadership.
A four-month investigation concluded she had breached the organisation’s social media rules by airing her concerns online.
It also ruled she had broken the ‘code of conduct’ by refusing to adhere to the Guides’ equality and diversity policy on transgender inclusion.
Ms Alcock was expelled when her membership of Girlguiding was withdrawn after she refused to unquestioningly agree to follow the new transgender rules.
She told The Mail on Sunday: ‘I wouldn’t discriminate against someone who said they wanted to change gender in the sense I wouldn’t treat them differently to any other child. But I believe gender is something created by society and it is about telling people how we think they should behave if they are a boy or a girl.’
Great quote OP.