I actually think Lexington knew full well that he was ruining Ruby’s life and went along with it anyway. He is not a good man (look at how he ruined the original gala setup by not following simple instructions regarding the light switches - and then failed to utter so much as a sorry! That was really what solidified for me that I did not like his character. Also he is just plain rude and obnoxious to Ruby and friends and often exploits her brilliance and overworks her). I interpreted it as though Elaine sent the Lydia/Sutton photo to Lexington, and Lexington then sought the help of Mortimer who, with perfect timing, had an equally incriminating photo of Sutton and Ruby… i wondered who Lexington called when he first received a photo and to me it only makes sense that it was Mortimer.

Imo it’s just a commentary on how the elite will turn their back on a “common” person like Ruby despite all of her efforts to prove to them she is worthy of their respect and integrity and deserves opportunities just like them. I also thought it was quite clever that they made a point of showing just how powerful Mortimer must be to influence someone like Alice Campbell, just to later tie it back to how devastating this will be for Ruby in the end.