Maybe the answer to the fencing au silva question is that he's attempting a two pronged approach by astroturfing a vexatious financial mismanagement complaint against M. through the club (paralleling the hearing scene in Skyfall) and a second complaint about her conduct during her tenure as head coach of team GB (which is actually kinda true, though she refuses to see it as anything other than "tough love" pushing her athletes to achieve their best).
Since Mallory is the treasurer he's in charge of working with the auditors to investigate the club finances side of it and he's initially very suspicious along with Clair Dowar (main lady in the hearing scene) as the main complainant, while Tanner is #M-til-I-die, and this creates a huge amount of tension in the club.
While this is happening Silva is fucking with Bond competitively and psychologically across half the globe. From @halfbaked00q's tags here (lightly abridged):
#cuz yes M is all detached and etc. esp w Bond. But #id argue in canon she is Not so much detached whenever Silva comes into the picture #so ig it's less abt the fact that someone is messing w Bond that is getting to her (rip Bond) #but that it's *Silva* specifically who is doing it....
(tags related to this post) so this is actually more like a three pronged attack where he's layering additional pressure onto M. by beating her repeatedly by proxy.
More from hb00q's tags (again, abridged):
#M kinda IS losing her step a bit #moving out of desperation rather than real strategy #I feel like QoS kinda shows us an M that isn't in fact infallible #some of it isn't her fault per se - the prob w having to take the bigger picture w things is you DO lose fidelity of detail #it doesn't affect his loyalty #[in] QoS. the like.. kind of.. resigned disillusionment. yk? of someone who has long ago had that like #moment when u realize ur parents are just human themselves and not these like towering infallible unshakeable keystones #but like.. part of you kind of still had some sort of residual child-like hope or w.e. that still managed to get let down just a bit.. #by this newest evidence of human failing. (*esp in a way that like fundamentally betrays you/who you are to some degree) #(*the like. unintentional but marked betrayal of when a parent shows that they do Not understand who you are actually #and their constructed idea of who they think you are betrays some level of thinks-less-than-the-best of you)
I do think this parent-to-adult-child strained relationship could work really well in something like this. Bond realising slowly that he doesn't have to #doitforher anymore. Like he should compete for himself, if he wants to. He doesn't like need to make her proud anymore (linking back to the "Mummy will be so disappointed." Silva line from the previous post, by the end that's not such a devastating blow for Bond.)
Maybe Silva and Bond are doing some low key fucked up hate sex/ just simmering sexual tension in the changing rooms at competitions and when Bond first comes to the conclusion that M. isn't everything he's built her up to be in his head he kind of nearly gives in to the allure of Silva and the appeal of destroying M. completely. But since 00q is endgame (for me) something something Q is able to somehow pull him back into the grey area of "she's done lots of unforgivable things but that she's not ontologically evil and deserves, like, — my brain is turning to soup at this point — gentle parenting type proportionate consequences for her actions, not complete and utter destruction.
final one, again from the tags:
#BUT if we Watsonian that. then I DO think it's interesting/compelling if Bond has this like kingmaker undercurrent to him yk?
Maybe the final straw that breaks M is Bond withdrawing his support, taking her aside and saying, "It's time."
So M is forced into retirement from coaching, but the financial thing is resolved so the club isn't forced to dissolve. Bond is able to beat Silva in the finals of the ~✨big endgame competition✨~ (this is a sports au after all) because of some flaw that he has in his technique from M's coaching (maybe this is something Bond also had and Q used against him to great affect and Moneypenny worked on coaching out of him). So see Silva may never really be free of M.
Then Q and Bond fuck nasty style in the showers I don't know I think this got a bit existential.
(or read this whole thing on ao3 if that's easier than jumping between posts xoxo)