My disagreement isn't with "proper" (whatever THAT means in a world that includes any semblance of HMRC) procedure, but rather the way with which it's being pursued. Nobody's trying to talk or reason or discuss, instead we have one genius literally planning to start assaulting anyone who does anything contrary to his plan, etc.
This is in character for Egan's character. His character does not care about being polite, or nice, he simply behaves in what he believes to be the most logical course of action; and, being a horribly deformed and likely insane
cultist, his logic can be rather questionable. Not that it's wrong, here: the threat of violence will likely make people simply give him space, rather than risking injury or taking dangerous actions as they intended.
What you're complaining about, here, is Egan making a character who behaves in a fashion you personally find offensive. You aren't complaining about the
character taking these actions, since you choice to complain OOC, you're complaining about
the real person who decided to set those actions up. Which, furthermore, shows bad taste on your part; strange and conflict-inspiring characters like Egan's make for a good story.
Yes, containing that thing may be a good idea. No, we do not really have any in-universe reason (yet, anyway) to start isolating it like it's a class 4 biohazard.
We know the last team died horribly, we know the scientists wanted guns ready, and we know that we know nothing about the risks. Furthermore, Egan's character is a cultist, and knows full well that Very Bad Things can be caused by 'simple' experiments like this one. There is plenty of IC justification for the character's actions.
The smart thing to do, in-universe, is probably to do exactly as the first few actions did: Be suspicious and check before touching, but otherwise do as the scientist said and move the stupid rodent and be done with everything.
No, that's the lazy and compliant thing to do. The smart thing is to assume the maximum risk that can be assumed without impeding ourselves, which is what the cultist did.
Alternatively I suppose we can throw caution to the wind and let the order of actions, dice rolls, and piecewise's truly remarkably malevolent game mechanics have at thee until we have attained an appropriate number of hilariously-improbable explosions, deaths, teleportations to the realms of darkness, etc.
The alternatives to your "moderate caution" plan are "no caution" (what you're describing), and "maximum caution" (what Egan did).
https://yourlogicalfallacyis.com/strawmanYou may want to dedicate some time to reading the rest of the stuff on that site. It's an encyclopedia of useful argumentative tactics which largely won't help against me.