Start iterating on transparency, it may be hard but you will see the great results and it will make everyone around collaborate much more.
You probably heard of the event [2] which occurred almost 2 years ago - people are still talking about it and we are really happy and impressed to see everyone, including us, learning from that experience.
I hope this non-technical suggestion will help you to think about a solution to your question. If your team is not used to this kind of openness, eventually they will like the positive feedback from the community (we see that as a small iteration :-)). A comment section at [2] may be the extra source of motivation.
Have a nice day,
Djordje - Community Advocate at GitLab
[1] https://about.gitlab.com/handbook/values/#transparency
[2] https://about.gitlab.com/2017/02/01/gitlab-dot-com-database-...
Like all culture changes it isn't complicated, just hard.