Sheesh, the whole Mille/Tommy thing was what, 2-3 years ago???? People get over things??!
I remember them slagging Tommy off, but even then I don't think they said a bad thing about Molly, and I know they said towards the end of LI something along the lines of "oh I know we didn't like Tommy as he was a jerk to our friend, but he seems genuine with Molly and they're cute" so obviously Millie didn't mind it even way back then.
Idk man, if I were Millie and had an ex from like 3 years ago who is now dating a face of a brand, I certainly would NOT mind my friend going to a social/business event that brand had??? It's not like she's f*cking Tommy, she's literally an influencer going to a PLT event, who cares