1.- That makes a lot of sense, thank you!
2.- Considering that the snake knew about that means and deliberately gave it to the mc could count as poisoning, but still makes more sense the irony of trying to reach immortality and finding a painful death instead.
3.- Hermes really COULD have done anything! We're talking about a god that has killed servants of Zeus and Hera, such as Argos to reach one of Zeus's victims, which was also being persecuted by Zeus's wife/sister. Even before the labyrinth he and Hades knew that a DENIZEN OF HADES was gonna get sent to a place that not only doesn't make any sense as even a punishment, just because that sadistic SOB, Athena, wanted to torture an innocent soul, one that was already sentenced to Hades by the court of the underworld, so basically Athena was violating both that court's mandate and Hades's sovereignty. Both really could have done a lot more, and they had the means to stop that from day 1. Not even that rule of Gods being limited in the new labyrinth would have power there as far as I can see, since literally a od like him already violated a lot of rules for the sake of her ego and pettiness.
Besides, the Argos snakes? WTF was he smoking? Most of the modern violence against Asterion can be and has been done thanks to that institution! Those snakes are great catalysts of sadistic ideas to the owners, doesn't matter if the ancient ones were worse, those Argois were the Perfect excuse for both Jean Marie and Clement to punish Asterion and pretend to be the victims there, both had greater outbursts against him and justified their horrible behavior on the Argois. Even when you go to the options of the ruthless ending, the snake asks you "why did you send Asterion out?" and all the possible options you can choose, are either terrible admissions of evil that can take the route in a horrible direction or even excuses secretly blaming Argos but not your own decision, which means, scapegoating the snake as the excuse for your bad choice making, at least that's how I saw it, would definitely be wrong, but my point stands that it was a dumb decision to create such an institution, with the worst excuse from Hermes, by the way.
And Hermes complained about his cenility when all the problem that cripples him is no small part his fault and Hades's, so I'm a little bit bitter.
Also, please forgive me for this long ass comment, I'm not being bitter against you or angry, man, I just can't resume this in a few lines, sorry!
PS: Also sorry for my terrible English and typos.