Which can only mean that 'recreational drugging' didn't count as 'shit being pulled'.
No - that was explained during the novel. The Red Court position was that Dresden, through his own carelessness, accidentally drank something designed to heighten the flavour of the blood the Red Court would be drinking. He wasn't even attacked - he merely did something that not even the most consciously host could have conceived him doing. And what does he do? He breaks the guest law by attacking his host for doing something that she was legally entitled to do.
If the poison had killed him then they probably would have had to pay a fine. Or maybe Bianca would have to been turned over to the White Council for Justice. There wouldn't have been a war over a low ranking member of the White Council dying... Now if it had been a Warden, then I could maybe see a war, just as there was a war over the death of Red Court Noble.
And it's the Accords that matter more than guest law because the invitation never promised safe passage. Blanca's house wasn't neutral ground but the party was happening under the Accords. Dresden was the White Council representative - invited under the accords - which is why he was thinking of going there even before the crap started to happen.
Bianca was just going to twist the wording of the accords to kill Dresden (White Council rep), kill Thomas and claim Justine (insulting White Court rep), trap Lea with an unbalanced gift (Winter Court rep), impress the Dragon (Accords freeholder), all under the eyes of the two cloaked figures (who might have represented another accord faction). If she was able to legally do all of that then she would have declared herself a Major Player.
Richard