But what I mean is that this is a situation where it would've made sense to bring Superman in. There's a world-threatening villain on the loose with Kryptonian ties, and the answers about her may lie in Superman's house. At the very least, if you plan to visit your cousin's residence, it's polite to ask them to escort you. Not to mention that Clark has been inviting Kara to the Fortress for years, so purely from a family standpoint, this would've been a big deal to him and he would've wanted to be there. I wish that, on this occasion, they had at least mentioned that he'd been contacted but had been unable to attend in person because, I dunno, giant robots were invading Metropolis and he couldn't get away.
I agree with all of that, I just think the show has been pretty consistent with the idea that Kara is determined not to involve him, even when it would make sense to do so. It's not exactly her most noble trait, but I think we've seen it often enough now that the show doesn't need to waste time explaining it anymore. It would just be redundant.