I’m having a similar issue, ACF strips double quotes when they’re entered into a textbox by the client. Doesn’t matter if the “New Lines” option is set to “Automatically add paragraphs, Automatically add <br>, or No Formatting.” The solution is to use single quotes but I really wish that wasn’t the case.
And to possibly help with your particular case, @michael-b, have you tried using a “typographer” or “curly” quote instead? Either the entity itself (”) or alphanumeric version (”
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