YEs but ask youself here. Why he dont give any Info out to Laz or roy or any other. Only pices? Tabbi is Rank 1 so usefull sure... But next is Why his stepsis. did not give any info out where she was? Think about it. And then you try to get Tabbi out of astrid blackmailing what happend ? so finger snip and MC can do it without train... F. baz gains more Learing then mc... dont see any grow in action only combat. so he is weak until end of update. so what now... ?
I'm pretty sure as much as Lazzaro is a decent source of info and a trustworthy, for now, ally, MC does have his doubts on what to share or not with him, precisely because there are still so many players inside the Hearth and unpredictability in it.
Not to mention, while Roy sure is working as a sort of double agent and getting accepted in House Luzato, and being a more reliable source of info from their insides, we still aren't entirely sure of his true nature or motives. Aside from knowing a bit of his past training in infiltration and as a spy, there's not much to him at all either.
I'm assuming with Stepsister you are referring to Nayla? Info on what? I'm pretty sure Nayla was as lost as anyone would be if you would be trapped in that sort of pocket dimension/prison, aside from having to work alongside Miss Arkada herself, Nayla is as lost as anyone who would be gone for that long and then feel like everything went passing by her. Aside from her duties of patroling and working on Sanctus, I'm pretty sure Nayla doesn't know much else from Tabby herself. Sure they are work colleagues and they do hang out every now and then, but like the full truth of Tabby's nature is still a mystery to her.
It's not so much a matter of snapping fingers and bam, things get done. If things weren't so messed up in the Hearth as they are in the first place, it would be very different. And, it's not like we haven't had training or did you completely miss that ENTIRE HORRIBLE painful nightmareish segment of us cutting our fingers, and slashing our arm just for the sake of "training" in this case, the regenerative ability of Bazrel's Vim?
True, Bazrel has been training, but it wasn't a thing until this very last/current update when he fully started getting into training his spirit and testing it to become more effective in battles and potential ambushes from powerful enemies.
Also you have to remember ANY way for magic or an aura to show, especially something like the one Bazrel has and it's a surefire way for anything and anyone wanting our heads. It's not so much being "weak" per se in the current circumstances, but more so trying to be careful and cautious, not only because to not die, but also because the Hearth, in any minute after future updates and by the end of this chapter might explode, in the sense of real shit happening, or more than it that hasn't already happened which could topple things altogether on our heads. We will only see when we get there.