They're sanitizing themselves in the midst of a confusing and overbearing situation when Claire tells Sherry she can come and she wants a shower anyway. It doesn't mean anything, it's just good characterization. The ending is less direct about it but still implies that there's a road ahead and "if there's more of this we have to do something about it." leaving it more open ended.
The original story is that the writer for RE2, Noboru Sugimura was about to flip out over the "Hey, it's up to us to take down umbrella" line, as it was something Kamiya added to the final cutscene because he felt it was badass, which caused Sugimura to revise the next thing he was working on: Code Veronica to have continuity with this motivation, but it was never anything they had discussed and there wasn't any discussed long-term plan to have an arc where Umbrella had to become the primary antagonist for a span of games. However, they started going that route until eventually Shinji Mikami shifted the series' direction after multiple scrapped prototypes for RE4 and the financially unsuccessful REmake, with the RE4 we all know and love, and then the Umbrella subplot was retconned with a timeskip and the idea that it had gone bankrupt instead.
That said, if these remakes are successful enough and Capcom sees an opportunity here, I think it's about time they fill in the gap between 1998 and 2003 in the timeline and show us the aftermath of Code Veronica and have some ensemble story and another classic-type outbreak scenario, maybe in the actual mountains of Arklay Mountains, some village or a neighbouring big city to Raccoon City, in which maybe Leon, Claire, Chris and maybe even Jill arrive during the outbreak already knowing they have to find some Umbrella higher ups and find tangible evidence of Umbrella's guilt, thus being able to shut them down and prevent further T-virus developments. You could even throw Wesker in there and establish some more of how he was characterized in 5 being that he is only concerned with himself and is slowly getting more obsessed with evolution.
I've always felt like, despite how RE never had particularly deep narratives, this gap in the timeline needed fixing and there's so many ways you could actually do it, and now having these modernized revisits of the classic-era RE being made, it seems like the perfect time to just say "Hey, RE8 takes place in year 2000" and all that follows thematically with that as well as making an all-new metroidvania style map full of puzzles, a new couple of signature monster variants but otherwise just more of these deadass RE2 Remake zombies and more of this fantastic gameplay.
