fleet omg I know *E X A C T L Y* what you mean, I have this exact same problem, massive hips especially at the top of the thighs I have about 3 pairs of trousers that I actually wanna wear ever and 0 of them are business attire. High five!
Luckily for me I work in a really casual dress code workplace so I'm sorry I can't advise with any authority on that. But they sound fine to me, I would say if you don't have to wear a tie then you probably should be fine wearing well fitting jeans? Especially if they are black or navy instead of classic blue. I imagine some places would actually prefer that you dress "well" rather than ill-fitting stuff that fits the dress code, but you could just have some backup cheap ugly slacks in case someone calls you out. And you can just be like, sorry I was using my best judgement.
In my experience people also generally don't know what to make of office dress codes for women, let alone curvy ones. In times where guys are expected to wear ÂŁ50 dress shirts and pants and blazers, women can be wearing some like ÂŁ2 turtleneck or boatneck they got at the grocery store and a charm bracelet and people will be like, that looks smart. When people think of "casual" they are almost always picturing like a dude in a military green t-shirt with holes in and some baggy cargo shorts and sandals or something. And they don't expect women to dress like men, but they cant expect us to wear star trek micro skirts cause that's discrimination (and bro... no seriously that is too much thigh from me) so we're there like ??? Plus omg, so many dress codes are starting to realise they don't allow for anything besides western white tradition so that's a whole thing.
I've also always been a massive tomboy so people seem to adjust their standards to me. I'll show up to a wedding in a sweater dress and some eyeliner and glittery sneakers and my friends will be like, "wow you look glam!" Like, not really but they appreciate the effort.