Setting aside the Debate as to whether Diketones are Harmful or Not for a second.
Where does the Issue of Advertising and Marketing come into Play?
Does an e-Liquid OEM Have the Right to say that something is Not In an e-Liquid they produce when it Actual Is?
And what happens when the OEM Knows that something is in an e-Liquid they Make/Sell when Asked by Consumers and or Interested Parties and then tells them it Isn't?
And Lastly, should e-Liquid OEM's/Sellers receive a "Pass" just because they are Part of the Vaping Community? Or do Individuals have a Right to Seek Remedies thru the Courts if Wrong Doings can be Shown to have Occurred?
I don't like seeing someone Bringing Forth a Lawsuit against an e-Liquid Company. And I agree, this Doesn't Help the e-Liquid Industry in general. I just wonder if we would be where we are Today if Five Pawns had just Told the Truth when First Asked if their e-Liquids contained either Da or AP?
Let's say OEM is told by its supplier (for a specific ingredient) that it does not contain the thing in question. And then OEM passes along information to consumers when asked directly if it is in there. I understand your question to be, "do they have a right to say that the something is not in the eLiquid when it may actually be in there?"
As that is how I understand both the question and the actual situation, I would say they do have the right. Me, I think it would be far better off to not mention that. But given how PC of an issue this was between 2010 and today, I'm not sure what response you give to customers that ask. Me, I'd go with it "it may be in there, I don't think it is."
Your inquiry of "what happens when OEM knows something is in eLiquid and they tell people it isn't" is something I think needs to be shown that they (being a collective unit of people) all knew the exact thing, and arguably knew at the same time or within same time frame.
Also does depend on the ingredient. Like say an eLiquid company is telling a customer that none of our products contain water, cause a customer is under impression that ingredients in all eLiquid is "water / water vapor." And a CSR person says, "nope, not in our products." But, the mixologist of same company actually knows that water is present in the ingredients at a molecular level. So if listing chemical composition, it would be known to all people that are part of "they" that tell customers what exactly is in the liquid. But as ingredients are only conveyed, then CSR is correct / honest to say that is not one of the ingredients, while technically mistaken given chemical makeup. CSR could even during a call, put customer on hold, and ask supervisor, "this customer is under impression we water down our product. Do we add water to our liquids?" And supervisor says no. Yet, mixologist knows the truth, but hasn't perhaps explained details of what precisely is occurring. So, perhaps not all of "they" are on same page.
Finally, individuals definitely have a right to seek remedies through courts for wrong doings. Hopefully their case is strong and not frivolous. You know, like basing an entire case on alleged potential harms, rather than actual harm.