@dropthevipers
Given (presumeably) he is well established in his career with a track record of not being a git then a "he said, she said" stand off with the work experience kid should only have one outcome. If I were him though I might seriously consider getting a bodycam to avoid misconstruction of any further encounters.
I support OPs DH against the staff member making allegations but strongly disagree with this post.
1- the staff member is not a "kid" - they are presumably at least 16, although I would assume 18 plus if they are a "student" - old enough to get married, have a job and pay NI. Feminists complain about calling women "girls" being degrading, and infantilisating someone to discredit them is exactly the same
2- they are not "the work experience kid" - they are a fully employed part time staff member with the same pay, duties and responsibilities as anyone else carrying out their role. The reason for them working part time (being a student) no less invalidates their right to full employment rights than someone working part time because they are disabled, or have young children or other caring responsibilities. Again, feminists have been very vocal and fought for years for part time workers (very often women) to have the same rights and opportunities as full time workers - including the right to express their opinions and make complaints without worrying they will be sacked for them.
3- the expectation that HR/senior management will (and worse, should) automatically side with the older, male, manager over the younger, part time, general worker is really, really not something we want to be encouraging!!!
This is why the FWR board has so many issues. The antagonism against trans issues has gone so far it seems to overwhelm everything else, and posters seem happy to invalidate all other women's rights we've been working for for years (centuries!) the second it comes to siding against trans rights supporters.
You can strongly disagree with both the opinions and actions of the staff member (as, to be clear, I do) without insulting, misrepresenting, and patronising them.