About the poisoning...
There are many strange things happening. First of all, the MC was poisoned as a child with the intend to build up a tolerance so he can survive such attack in the future... well at least i think so, as others do too in this thread.
but to be poisoned by a specific poison doesnt help you tolerate every poison... so at the dinner, it had to be the very same poison the MC gets as a child by his mother... very very big coincidence hence the fact that there are thousands really potent poisons in the world. So no, that is no coincidence... the MCs mother must have known that the MC will get poisoned someday in the future with this specific poison. My guess? The contract was already made at that time. Like a life-dept (you owe your child to the DeLucas) or something like that. And the posion is a special poison used by DeLuca members and MCs mother prepared him for that, cause she predicted that some people in the circle of the DeLucas would try to kill him someday with it.Why? Dunno... but MCs mother was a serpent herself just like Cordia, so much is clear. So it wouldnt be a surprise if she knows which poison they would use...
who done it? Difficult to say at this point, there are really no clues at all... it could be that the person who has done it didnt even appeared in the game so far. We didnt even met all of the 4 serpents so far. Maybe it was one of them? It could be whole group of people to... doesnt have to be a single person.
I have a little bit of trust issues with Wilfred though... he is making some serious decisions himself, over the head of Cordia. She still aproves those things... but to me it appears that Wilfred is not really pleased with Cordia as the leader of the DeLucas. Maybe he is plotting something and sees the MC as a threat in the long run? Even if he likes him in a way.
OR maybe the poisoning of the MC was just a test to see if the MC is the "real deal". Could be that Wilfred knows about the preparation during MCs childhood and was testing the "waters" to see if the MC is prepared enough to even survive this poison?
And so many people around the DeLucas and outside of the DeLucas "watched" the mc since he was a child... and what happened to his parents anyways? There are countless possibilities so far... and so many unknown things regarding MCs history and destiny...
There are just not enough hints or suspicious character so far in the game to make even a wild-guess who could have done it iam afraid... could be everyone or no one, cause the persons behind this didnt make their appearence yet.
Yeah i thought a long time about that too, but really i cant drop a name so far for the poisoning... I have my trust-issues with Wilfred, but it wouldnt really fit in any way that he had done it... at least i cant think so.
Either way, the one who did the poisoning must be the same person who sabotaged the car at the very start of the game too... or maybe we arent even talking about one person, could be a whole group of people too... *shrug* nah cant really enclose this issue so far. And i guess we will not get any hints in that direction for a long long time... as i see it, the game is still in its early stages... i mean... fuck, just look at the contract list at Wilfred, we are a Soldato still in rank D... if the plan is to go all the way up, this game will get so freaking big....
*edit* well one figure comes to mind though... Cesarino from the prologue. He dislikes the MC from the start (cause Cesarino is the average prick) pretty sure he is somewhat involved, he could even have sabotaged the car. Maybe he was recruited by another group/family where he thinks he can climb the ranks faster? but in someway... its would be to obvious/easy i think.