Yes, the huge irony is that whilst they are posturing about being 'inclusive' all the evidence points to Oxfam employees being the least diverse, most cliquey, rigidly group-thinking people you could possibly encounter.
If they'd actually had any diversity in their paid staff, a few older employees not steeped in queer theory for example, some working class people, some people with a passing knowledge of history and past Nazi propaganda, people who were in any way willing to question or think of the wider context, there is no way this would have gone out without someone saying 'hang on a minute....'.
The very fact this was signed off shows how lacking in diversity of thought their core employees are. And ultimately, even if the multiple rape allegations and misogyny didn't exist, if your employees are completely incapable of even predicting the backlash to something like this, I don't think they're going to be especially effective in provided the aid needed to people in other countries who are suffering and whose lived experience is even further removed from theirs than UK feminists.