There's no way that's happening, everyone else is too good-hearted.
Also given the overall tone of the story this is probably a setup for those two to learn a valuable lesson.
Still wondering whether this will become a "companions of the week" kinda story or a "mom accidentally adopts a bunch of new sons/daughters" kinda story.
yeah - we already got the little bit of flash-backstory wherein the main "bratty" girl is shown as having been told that she couldn't become an adventurer as a child - and that she saw it as her ticket to freedom and self-empowerment & a chance to get out of poverty.
So her abrasiveness is easily explainable as "desperation" - and that she sees the others as being too carefree and laid-back about something she's taking exceedingly seriously for entirely valid, if personal, reasons.
That sort of discrepancy when one person cares deeply about something, and gets upset when others seemingly treat that same thing in a rather flippant manner,
is understandable. A not-too-dissimilar example would be when a student cares about their grades, and ends up simply doing all of the work in a group project because all of their partnered classmates don't care or are goofing off/spending "work time" joking around and not being serious.
That
will rub you the wrong way given enough time, and if this isn't her first rodeo of dealing with an ad hoc party wherein she and maybe Saza were the only two who were fully invested in ranking up, she probably has come to see all "newbies" as fair-weather adventurers and just dismisses them all.
And
that mindset, coming into this group and this scenario, becomes a prime moment for some potential "leveling up in life", as it were. And like you said - no one in the group is actually cruel or mean; Lucy and Saza are just serious and desperate (I assume Saza's in the same position as Lucy), and the others' attitudes
did make it seem like they didn't care as much.
But now she's seen how strong Tachua is, and that will segue (hopefully) into Lucy finding more constructive ways to progress and achieve what she wants, that involve more active understanding and cooperation with her peers.
And honestly, this is a great title for that sort of storytelling.
We already have a Literal Maternal Protagonist, who seeks to protect others around her and wants everyone to be happy and safe. Turning these sorts of things into "growing up" lessons is entirely on-brand and I think could even be done well by the author.