Personally I don't see any promises of absolute randomness from Blizzard. I mean they have to report odds with regards to pack purchases by law and do so. But I don't see any reason for them to be bound to absolute randomness. When cards don't quite work for a meta or game I could see them doing small tweaks to how the card plays without disclosing rather then remove the card or nurf it.
I am not saying that this is occurring here. But blind trust is a corporation is arguably drinking more koolaid then questioning and checking occasionally.
Obsessive questioning is a waste of time but obsessive trust and mocking of questioning is meh.